thinking oil filters, like tires, probably are made by 3 or 4 different companies and then just branded by the retailer. Like the hundreds of different tire brands you know? All made by the big 3 or whatever tire factories. I'm looking with Google hoping to find some facts to back up my speculation and see hundreds of "manufacturers" for oil filters, filtration products, stuff like that. I just can't imagine there are that many factories that put together oil filters. I know Amsoil filters are supposed to be good but which company makes them? On the shelf in my garage I have K&N spin-ons, Purolator,NAPA ( Balkamp?) Amsoil , sheesh, probably more if I was better organized . I just purchased 6 NAPA "Gold" spin-ons for the bike and he let me have them for $7.79 + tax--great deal for sure. Then I go to Kragen to get oil and see the K&N's there for $13.90 , also Mobil1 filters, Wix, FRAM :Dan0: Purolator and Pennzoil. Sheesh, how many different factories can there be? Do I want to spend almost $14 on a filter that's made in the same place, by the same method, same materials, as a $7 filter? I think there must be some conspiracy going on just to keep me ignorant- it's working--I don't know what to do. I want to run a quality product , no point in saving 6 bucks if it's at the price of little chunks of metal floating right through the filter and back by the place where they originated over and over. I need some facts and I'm not sure where to get them. At least with tires I can "feel" some difference and make a decision based on that but with an oil filter how do I know what I'm getting for my money?