I got a great deal at my local NAPA dealer on the Sport Truck Wix filters in the Ford part number 51515ST.Bought out his stock of eleven filters after I put one on my Jeep 4.0L and liked the cold start and flow parameters according to my dashboard gauge(which is not all that accurate,but thats what I go by).On the side of the filter box the claims are as follows 1.High performance "TuffGlass" media 2.Metal end caps for strength 3.Perforated spiral steel center tube for the highest collapse strength in the business 4.Magnetic coiled retainer spring 5.Silicone sealing gasket and anti drainback valve 6.Precision-engineered by-pass valve (bottom Ford spec type)It does look pretty cool when I cut one open,has to do it...I'm sick...they seem to be a very good quality filter in my opinion.Filtration claims on the box are 99.6% on the single pass,don't list for the multiple pass and they give the capacity of contaminant and weighed average also as compared to Purolater,A.C Delco,Fram,Quaker State.I like em'..got them for $6.50 apiece Can.