Picked up a couple of these mainly because I had never seen one before ... the HP17 is the 20x1.5 mm thread Honda / Nissan / Subaru etc. application. They were $ 10 CDN , which is about $ 4.00 less than a Fram Ultra 7317. These filters are advertised as HIGH FLOW / HEAVY DUTY, and come with a Subaru friendly 22 psi by-pass. This model does not have the screened by-pass valve advertised for other models. Efficiency is listed as 94% @ 20 mu. This is the first Fram I have seen with a louvered core. Louvers look ok, but if you hold them up under a light ( have to gut the filter to do it ... ) , they look good. Seems to be WAY MORE louvers than there are holes in a comparable Fram Ultra.