Is the location of the bypass valve that important? After cutting open many of my used MC filters with the bypass at the top of the filter Ive never found any residue at the bottom(dome)that would have been sucked into the system with a filter that has a dome end bypass.I run only 5w20 as per specs of the ford cars I own and dont think the filter hardly if ever goes into a bypass mode. Just wondering since most after market filters have the dome bypass location and Im looking for a longer OCI filter instead of the standard MC filter.
Bypass location
- Thread starter dinkydau
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IMO, no.
Lots of people make lots of posts after dissecting oil filters and proclaiming one is better than the other. Leaf vs coil spring, dome vs thread end bypass, metal vs plastic vs fiber endcaps, perforated metal cores vs plastic, etc...
The truth is, most cars will never experience a lubrication-related failure due to the oil filter design. I personally think a silicone ADBV is better than a nitrile one to eliminate startup noise and retain oil in the system. Even though the momentary rattle is unlikely to cause any sort of failure.
How many miles are you currently putting on an OCI and why do you think your current Motorcraft filter isn't up to the task?
FWIW, your oil filter spends plenty of time in bypass mode, especially at startup.
Lots of people make lots of posts after dissecting oil filters and proclaiming one is better than the other. Leaf vs coil spring, dome vs thread end bypass, metal vs plastic vs fiber endcaps, perforated metal cores vs plastic, etc...
The truth is, most cars will never experience a lubrication-related failure due to the oil filter design. I personally think a silicone ADBV is better than a nitrile one to eliminate startup noise and retain oil in the system. Even though the momentary rattle is unlikely to cause any sort of failure.
How many miles are you currently putting on an OCI and why do you think your current Motorcraft filter isn't up to the task?
FWIW, your oil filter spends plenty of time in bypass mode, especially at startup.
Right now Im at 4k on PYB and a MC filter at the 6 month mark. Looking to go with PP or QSUD and a one year OCI with about 7.5 to 10k miles. Not thinking that the MC910S isnt up to the task mileage wise just think I can do better in the filtration with an after market filter. Everything Ive read says the MC is around 97% effective. I have run a P-1 which is rated at 99% for over 6.5K with QSUD but when I cut it open the end cap fell off the filter element in my hand and that didnt impress me at all. Thinking of trying a Fram Ultra,Amsoil or RP. For a once a year item the cost isnt much of a concern to me.
Understand what you are saying about the silicone ADBV but the filter mounts verticle so thats not a problem to me since it cannot drain back.
Understand what you are saying about the silicone ADBV but the filter mounts verticle so thats not a problem to me since it cannot drain back.
Base end bypass is "theoretically" better. In the dome-end bypass scenario the lubricant flow pattern will wash any large debris off the pleats and also off the dome bowl then flow right into the engine causing abrasive wear of bearings, etc. many bearing spec diametrical clearance of under 1.5 mils which will show a running clearance of well under 1.0 mil(25 microns). Plain Bearing wear + valve stem "bushing" are the first areas of abrasive wear to render an engine out of service at end of life. This is one of the reasons I prefer WIX construction for med and larger form factor aftermarket filters.
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My opinion, based on research and study, is that bypass location is not terribly important. It's certainly "theoretically better" to have a base end valve but the realities are:
-Bypass events in the normal course of things are infrequent, assuming you are not one of those thicker oil is better guys and do a lot of cold starts. Cold (cold can be defined as low ambient temps but also just a start at the oils 40C temp) starts and thick oil is the most common cause of bypass events. Overly thick oil for the temperature increases the likelihood of a bypass event, and it's duration/extent.
-Contaminants on the media are often embedded and will not be washed off.
-Contaminants on the media will be also locked into place onto the media by differential pressure.
-Bypass opening events are most often only partial openings (if not just a momentary cracking of the valve) so the total flow is divided between the bypass valve and the media, so it' isn't usually a case of ALL flow going to bypass, just a portion. The amount of contamination that may escape the filter will therefore be a small in most cases.
-Modern engines, once broken-in, seldom shed large amount of metal unless there is a failure occurring (in which case filtration, or lack thereof is your least worry). The amount, size and characteristics of the contaminants is likely to be in the low risk category for being able to cause much harm, especially if the amount bypassed is small. It will be recaptured the next time thru.
-Even with a base end bypass, it's still possible for contaminants to pass by the filtering media.
-In my interviews with experts on this topic, more than a few engineers in the oil filter industry note the style of valves commonly used in base end bypass systems are less reliable than the types used for dome end bypass. I have no way to verify/qualify those statements beyond what I was told, but they have come from five engineers so far. All agree that a base end bypass is "preferable" but when all the factors are balanced, it doesn't count for much in the real world. For myself, I give this a fair bit of weight and I put the bypass location design characteristic much lower on my list of priorities when comparing filters.
The bottom line is to minimize bypass event AMAP by using the correct grade of oil for the climate and operational situation (e.g. with cold starts being the most likely cause of bypass in a short hopped rig with lots of starts, a light oil or an oil with very good cold flow will help minimize bypass), minimizing cold starts as much as possible (or use block or pan heaters), go easy on the engine until the oil warms up (high revs and cold starts are the SURE ways to induce bypass). You can also choose a filter with a higher bypass setting but that requires a lot of cogitation and some knowledge of how the lubrication system works in the particular engine.
-Bypass events in the normal course of things are infrequent, assuming you are not one of those thicker oil is better guys and do a lot of cold starts. Cold (cold can be defined as low ambient temps but also just a start at the oils 40C temp) starts and thick oil is the most common cause of bypass events. Overly thick oil for the temperature increases the likelihood of a bypass event, and it's duration/extent.
-Contaminants on the media are often embedded and will not be washed off.
-Contaminants on the media will be also locked into place onto the media by differential pressure.
-Bypass opening events are most often only partial openings (if not just a momentary cracking of the valve) so the total flow is divided between the bypass valve and the media, so it' isn't usually a case of ALL flow going to bypass, just a portion. The amount of contamination that may escape the filter will therefore be a small in most cases.
-Modern engines, once broken-in, seldom shed large amount of metal unless there is a failure occurring (in which case filtration, or lack thereof is your least worry). The amount, size and characteristics of the contaminants is likely to be in the low risk category for being able to cause much harm, especially if the amount bypassed is small. It will be recaptured the next time thru.
-Even with a base end bypass, it's still possible for contaminants to pass by the filtering media.
-In my interviews with experts on this topic, more than a few engineers in the oil filter industry note the style of valves commonly used in base end bypass systems are less reliable than the types used for dome end bypass. I have no way to verify/qualify those statements beyond what I was told, but they have come from five engineers so far. All agree that a base end bypass is "preferable" but when all the factors are balanced, it doesn't count for much in the real world. For myself, I give this a fair bit of weight and I put the bypass location design characteristic much lower on my list of priorities when comparing filters.
The bottom line is to minimize bypass event AMAP by using the correct grade of oil for the climate and operational situation (e.g. with cold starts being the most likely cause of bypass in a short hopped rig with lots of starts, a light oil or an oil with very good cold flow will help minimize bypass), minimizing cold starts as much as possible (or use block or pan heaters), go easy on the engine until the oil warms up (high revs and cold starts are the SURE ways to induce bypass). You can also choose a filter with a higher bypass setting but that requires a lot of cogitation and some knowledge of how the lubrication system works in the particular engine.
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I like the base plate located bypass. Chevy got it right by putting the bypass in the engine block, thereby making the filter much simpler.
Originally Posted By: TallPaul
I like the base plate located bypass. Chevy got it right by putting the bypass in the engine block, thereby making the filter much simpler.
Yep and the bypass is potentially "tuneable" as well, IIRC. My old 6.9L diesel has an engine mounted bypass also. Potentially it's tunable but it's not really serviceable. IIRC (it's been a while since I've been in a smallblock) you can alter the bypass setting by shims or spring changes. Please correct me if I'm wrong about that.
I like the base plate located bypass. Chevy got it right by putting the bypass in the engine block, thereby making the filter much simpler.
Yep and the bypass is potentially "tuneable" as well, IIRC. My old 6.9L diesel has an engine mounted bypass also. Potentially it's tunable but it's not really serviceable. IIRC (it's been a while since I've been in a smallblock) you can alter the bypass setting by shims or spring changes. Please correct me if I'm wrong about that.
Originally Posted By: ARCOgraphite
Base end bypass is "theoretically" better.
It really depends on the filter's orientation. A base end bypass wouldn't be very good on a filter that is mounted base down (ie, 4.0L V6 Tacoma). A dome end bypass would be better in that application.
If a filter is mounted horizontally, it doesn't really matter IMO. If mounted base end up, then yes a base end bypass would theoretically be better.
Base end bypass is "theoretically" better.
It really depends on the filter's orientation. A base end bypass wouldn't be very good on a filter that is mounted base down (ie, 4.0L V6 Tacoma). A dome end bypass would be better in that application.
If a filter is mounted horizontally, it doesn't really matter IMO. If mounted base end up, then yes a base end bypass would theoretically be better.
Base end bypass is required for the ford 4.6 etc, because the filter mounts sideways. Between runs accumulated crud drops off the filter paper and collects allong the lower side of the filter. Under some circumstances when the bypass opens, crud can be washed from the lower side and up into the engine. Take a look under the aluminum cap on the oil end of the valve train and you find a very small passage the oil has to go through to lube the cam. Blocking this oriface causes no end of problems.
Originally Posted By: dickwells
Base end bypass is required for the ford 4.6 etc, because the filter mounts sideways. Between runs accumulated crud drops off the filter paper and collects allong the lower side of the filter. Under some circumstances when the bypass opens, crud can be washed from the lower side and up into the engine. Take a look under the aluminum cap on the oil end of the valve train and you find a very small passage the oil has to go through to lube the cam. Blocking this oriface causes no end of problems.
If the filter is horizontal, would not a base and dome end bypass be on approximately the same level?
Base end bypass is required for the ford 4.6 etc, because the filter mounts sideways. Between runs accumulated crud drops off the filter paper and collects allong the lower side of the filter. Under some circumstances when the bypass opens, crud can be washed from the lower side and up into the engine. Take a look under the aluminum cap on the oil end of the valve train and you find a very small passage the oil has to go through to lube the cam. Blocking this oriface causes no end of problems.
If the filter is horizontal, would not a base and dome end bypass be on approximately the same level?
One would expect the oil to pass over the dirty filter element on its way to the dome end bypass, potentially picking up crud on the way. It would not do that on a base plate mounted bypass. So I don't know that orientation of the filter really mattera. But in reality, with the base plate bypass location, the oil is shooting in at high pressure. Wouldn't it create a good deal of turbulence alongside the dirty filter element as it comes in and has to make a 180 to the bypass location? So it may be a non issue. Yet they still make filters with the base end bypass. It does seem that the base end bypass is much more substantially made. All the dome end bypass valves on filteres I have disassembled seem cheap and flimsy.
once i had 392 hemi in a 59 ply, with the filter 4 ft a way from the stock location, large hose 1/2" id, i had NO trouble.
Originally Posted By: TallPaul
One would expect the oil to pass over the dirty filter element on its way to the dome end bypass, potentially picking up crud on the way.
Need to realize that when an oil filter goes into bypass, there is also still oil flow going through the media .. unless the media is totally blocked. On a filter with a dome end bypass, the oil will flow into the base and will try to flow through the media before flowing through the bypass opening. Only time there might be a problem is if the filter is so loaded up that crud actually falls out of the media and collects in the dome end with the filter orientated base up. IMO, on engines that are in good condition and if the filter has been changed on a regular basis, the chances of crud falling out of the media and collecting near the bypass valve is very low.
One would expect the oil to pass over the dirty filter element on its way to the dome end bypass, potentially picking up crud on the way.
Need to realize that when an oil filter goes into bypass, there is also still oil flow going through the media .. unless the media is totally blocked. On a filter with a dome end bypass, the oil will flow into the base and will try to flow through the media before flowing through the bypass opening. Only time there might be a problem is if the filter is so loaded up that crud actually falls out of the media and collects in the dome end with the filter orientated base up. IMO, on engines that are in good condition and if the filter has been changed on a regular basis, the chances of crud falling out of the media and collecting near the bypass valve is very low.
dnewton3
Staff member
Originally Posted By: Jim Allen
My opinion, based on research and study, is that bypass location is not terribly important. It's certainly "theoretically better" to have a base end valve but the realities are:
-Bypass events in the normal course of things are infrequent, assuming you are not one of those thicker oil is better guys and do a lot of cold starts. Cold (cold can be defined as low ambient temps but also just a start at the oils 40C temp) starts and thick oil is the most common cause of bypass events. Overly thick oil for the temperature increases the likelihood of a bypass event, and it's duration/extent.
-Contaminants on the media are often embedded and will not be washed off.
-Contaminants on the media will be also locked into place onto the media by differential pressure.
-Bypass opening events are most often only partial openings (if not just a momentary cracking of the valve) so the total flow is divided between the bypass valve and the media, so it' isn't usually a case of ALL flow going to bypass, just a portion. The amount of contamination that may escape the filter will therefore be a small in most cases.
-Modern engines, once broken-in, seldom shed large amount of metal unless there is a failure occurring (in which case filtration, or lack thereof is your least worry). The amount, size and characteristics of the contaminants is likely to be in the low risk category for being able to cause much harm, especially if the amount bypassed is small. It will be recaptured the next time thru.
-Even with a base end bypass, it's still possible for contaminants to pass by the filtering media.
-In my interviews with experts on this topic, more than a few engineers in the oil filter industry note the style of valves commonly used in base end bypass systems are less reliable than the types used for dome end bypass. I have no way to verify/qualify those statements beyond what I was told, but they have come from five engineers so far. All agree that a base end bypass is "preferable" but when all the factors are balanced, it doesn't count for much in the real world. For myself, I give this a fair bit of weight and I put the bypass location design characteristic much lower on my list of priorities when comparing filters.
The bottom line is to minimize bypass event AMAP by using the correct grade of oil for the climate and operational situation (e.g. with cold starts being the most likely cause of bypass in a short hopped rig with lots of starts, a light oil or an oil with very good cold flow will help minimize bypass), minimizing cold starts as much as possible (or use block or pan heaters), go easy on the engine until the oil warms up (high revs and cold starts are the SURE ways to induce bypass). You can also choose a filter with a higher bypass setting but that requires a lot of cogitation and some knowledge of how the lubrication system works in the particular engine.
That was a thoughtful, complete description of the reality. So very much agree all the way around with your comments.
And I'll add this; what of the engines that have no bypass in the filter, and eschew them for the bypass in the block? Are we to contend that they are superior/inferior based upon their location?????
The real world data shows that this is a moot point; it does not really manifest into statistically significant differences that shift the wear data whatsoever. What tiny bit it might matter (and I'm not saying it does, only that it might), would be TOTOALLY LOST in the typical normal wear variation of any single engine or engine family.
As Jim said, in theory it might matter.
In reality, it does not.
My opinion, based on research and study, is that bypass location is not terribly important. It's certainly "theoretically better" to have a base end valve but the realities are:
-Bypass events in the normal course of things are infrequent, assuming you are not one of those thicker oil is better guys and do a lot of cold starts. Cold (cold can be defined as low ambient temps but also just a start at the oils 40C temp) starts and thick oil is the most common cause of bypass events. Overly thick oil for the temperature increases the likelihood of a bypass event, and it's duration/extent.
-Contaminants on the media are often embedded and will not be washed off.
-Contaminants on the media will be also locked into place onto the media by differential pressure.
-Bypass opening events are most often only partial openings (if not just a momentary cracking of the valve) so the total flow is divided between the bypass valve and the media, so it' isn't usually a case of ALL flow going to bypass, just a portion. The amount of contamination that may escape the filter will therefore be a small in most cases.
-Modern engines, once broken-in, seldom shed large amount of metal unless there is a failure occurring (in which case filtration, or lack thereof is your least worry). The amount, size and characteristics of the contaminants is likely to be in the low risk category for being able to cause much harm, especially if the amount bypassed is small. It will be recaptured the next time thru.
-Even with a base end bypass, it's still possible for contaminants to pass by the filtering media.
-In my interviews with experts on this topic, more than a few engineers in the oil filter industry note the style of valves commonly used in base end bypass systems are less reliable than the types used for dome end bypass. I have no way to verify/qualify those statements beyond what I was told, but they have come from five engineers so far. All agree that a base end bypass is "preferable" but when all the factors are balanced, it doesn't count for much in the real world. For myself, I give this a fair bit of weight and I put the bypass location design characteristic much lower on my list of priorities when comparing filters.
The bottom line is to minimize bypass event AMAP by using the correct grade of oil for the climate and operational situation (e.g. with cold starts being the most likely cause of bypass in a short hopped rig with lots of starts, a light oil or an oil with very good cold flow will help minimize bypass), minimizing cold starts as much as possible (or use block or pan heaters), go easy on the engine until the oil warms up (high revs and cold starts are the SURE ways to induce bypass). You can also choose a filter with a higher bypass setting but that requires a lot of cogitation and some knowledge of how the lubrication system works in the particular engine.
That was a thoughtful, complete description of the reality. So very much agree all the way around with your comments.
And I'll add this; what of the engines that have no bypass in the filter, and eschew them for the bypass in the block? Are we to contend that they are superior/inferior based upon their location?????
The real world data shows that this is a moot point; it does not really manifest into statistically significant differences that shift the wear data whatsoever. What tiny bit it might matter (and I'm not saying it does, only that it might), would be TOTOALLY LOST in the typical normal wear variation of any single engine or engine family.
As Jim said, in theory it might matter.
In reality, it does not.
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Originally Posted By: dnewton3
And I'll add this; what of the engines that have no bypass in the filter, and eschew them for the bypass in the block? Are we to contend that they are superior/inferior based upon their location?????
From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
And I'll add this; what of the engines that have no bypass in the filter, and eschew them for the bypass in the block? Are we to contend that they are superior/inferior based upon their location?????
From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
Okay, just read Jim Allen's long post and agree he makes a lot of sense. In fact, I recently asked someone at Baldwin filters about this and was told
Quote:
I understand your thinking and agree in theory it may be true that the front-end bypass would be better for that reason. We are unable to quantify, with lab testing, that there is any difference between the front or rear locations.
Quote:
I understand your thinking and agree in theory it may be true that the front-end bypass would be better for that reason. We are unable to quantify, with lab testing, that there is any difference between the front or rear locations.
An interesting observation made in this old thread ("wrong" being relative to Ford specification of the base end):
Originally Posted By: quadrun1
Another interesting thing that I've observed is that if your filter's thread size is not 3/4-16, the valve is most likely at the "wrong" end. (Mitsubishi, Honda, many others...)
This makes me wonder if the base end bypass is an older design, before all these new thread sizes came in (assuming all were 3/4-16 once upon a time).
Anyway, I think I am ready to consider and even use the dome end bypass now.
Originally Posted By: quadrun1
Another interesting thing that I've observed is that if your filter's thread size is not 3/4-16, the valve is most likely at the "wrong" end. (Mitsubishi, Honda, many others...)
This makes me wonder if the base end bypass is an older design, before all these new thread sizes came in (assuming all were 3/4-16 once upon a time).
Anyway, I think I am ready to consider and even use the dome end bypass now.
Quote:
From ZeeOSix:From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
Good observation. We've been stepping over that very obvious point as we heatedly debate the position of the filter bypass. But we must also consider how the engine bypass works. In the case of my 6.9L diesel, the bypass is in the filter base, so when it bypasses, it bypasses into the outflow, so it's the same as if it was built into the filter.
Quote:
From TallPaul: Anyway, I think I am ready to consider and even use the dome end bypass now.
Thanks for posting that quote from the Baldwin guy. That makes six oil filter people now that have expressed more or less the same thing.
Bottom line, I'd use a base end filter over a dome end (note that these two terms will make filter industry pros scratch their heads because they don't use them) if all the other factors I regard as more important met my criteria. So.... Fram... make me an Ultra with a base end bypass and I'll be in heaven.
From ZeeOSix:From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
Good observation. We've been stepping over that very obvious point as we heatedly debate the position of the filter bypass. But we must also consider how the engine bypass works. In the case of my 6.9L diesel, the bypass is in the filter base, so when it bypasses, it bypasses into the outflow, so it's the same as if it was built into the filter.
Quote:
From TallPaul: Anyway, I think I am ready to consider and even use the dome end bypass now.
Thanks for posting that quote from the Baldwin guy. That makes six oil filter people now that have expressed more or less the same thing.
Bottom line, I'd use a base end filter over a dome end (note that these two terms will make filter industry pros scratch their heads because they don't use them) if all the other factors I regard as more important met my criteria. So.... Fram... make me an Ultra with a base end bypass and I'll be in heaven.
That was a "Service Engineer" who stated their lab testing finding. So it is front end and rear locations. Wow, that just does not sound like professional terminology.
Now the big question. Why do they have a front end bypass on any of them. If Ford requires it, why is Baldwin's FL1A (Baldwin B2) filter with it, but their FL400s (I don't have the Baldwin # on this) is without. Both are ford and both have front end bypass in Wix. Neither have front end bypass in Federated (Hastings made).
Now the big question. Why do they have a front end bypass on any of them. If Ford requires it, why is Baldwin's FL1A (Baldwin B2) filter with it, but their FL400s (I don't have the Baldwin # on this) is without. Both are ford and both have front end bypass in Wix. Neither have front end bypass in Federated (Hastings made).
Originally Posted By: Jim Allen
Quote:
From ZeeOSix:From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
Good observation. We've been stepping over that very obvious point as we heatedly debate the position of the filter bypass. But we must also consider how the engine bypass works. In the case of my 6.9L diesel, the bypass is in the filter base, so when it bypasses, it bypasses into the outflow, so it's the same as if it was built into the filter.
In your 6.9L diesel, even though the engine's bypass valve is in the filter's base, it's still not in the filter at all (right? ... if I understand you correctly). Boils down to if the bypass filter is actually inside the oil filter or not.
Even an oil filter with a base end bypass, the valve is still inside the filter where debris is collected. With a base end bypass inside the filter, it's still possible depending on the filter's orientation to have debris flow through the bypass if it opens. Example I gave was using a filter with a base end bypass on a 4.0L V6 Tacoma engine which has the filter mounted perfectly base down. If the filter was so loaded up that debris fell out of the media and down on the base of the filter where the bypass valve was, upon cold start-up that debris could flow through the base end bypass valve and into the engine. But if the bypass was in the block, or in the filter mount, that debris couldn't flow through that bypass valve because the bypass valve is external to the oil filter.
Quote:
From ZeeOSix:From a "possible engine contamination during bypass event" perspective, the filter bypass valve built into the block is the best configuration, as it gives zero chance for any collected debris in the filter from entering the engine during a bypass event.
Good observation. We've been stepping over that very obvious point as we heatedly debate the position of the filter bypass. But we must also consider how the engine bypass works. In the case of my 6.9L diesel, the bypass is in the filter base, so when it bypasses, it bypasses into the outflow, so it's the same as if it was built into the filter.
In your 6.9L diesel, even though the engine's bypass valve is in the filter's base, it's still not in the filter at all (right? ... if I understand you correctly). Boils down to if the bypass filter is actually inside the oil filter or not.
Even an oil filter with a base end bypass, the valve is still inside the filter where debris is collected. With a base end bypass inside the filter, it's still possible depending on the filter's orientation to have debris flow through the bypass if it opens. Example I gave was using a filter with a base end bypass on a 4.0L V6 Tacoma engine which has the filter mounted perfectly base down. If the filter was so loaded up that debris fell out of the media and down on the base of the filter where the bypass valve was, upon cold start-up that debris could flow through the base end bypass valve and into the engine. But if the bypass was in the block, or in the filter mount, that debris couldn't flow through that bypass valve because the bypass valve is external to the oil filter.
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