So I bought this oil filter at West Marine last time I was there getting some Starcool (propylene glycol coolant). Wasn't really any more expensive than your typical PH2 style filter, and I was intrigued by the box saying 10 microns, when every other box said 20 microns. Nice thick can, nitrile gasket so I won't be using it on my Subaru in the winter, because I have had them blow out before. But for Spring/Summer/Fall it looks like a nice filter. Made in Taiwan. Has an unusual looking bypass valve. The question is, does it really filter down to 10 microns? Do we even know anything about this filter or who made it? And if it does filter that fine, what efficiency rating? Interestingly enough it is the only filter out of all of the ones they had that listed that small of a micron rating. The Sierra filters can vary a lot in construction and country of origin depending on what application they are for. I have seen USA, Japan, Thailand, Taiwan, China, Mexico, Germany, Tunisia, Malaysia. The Quicksilver filters also sold at West Marine also vary in country of origin. I am a big fan of the 7317-equivalent filter for some of the Honda, Yamaha, Nissan outboards. Very nice soft silicone ADBV, made in Taiwan I believe, metal core with holes, thick can, nice gasket. I use them on the neighbor's QR25DE, as they only cost about 8 dollars and are very good quality. Quicksilver cross reference for this Sierra is listed on top of the box, third picture.