Decided to find out from purolator, what micron rating the 99% claim was filtering. I was kind of shocked that they’re the same as the boss filters…46 micron rating. Insane
One way to make an "extended" use oil filter is to make the efficiency lower (same goes with the Wix XP and Purolator Boss).
On the opposite side of the spectrum, oil filters like the OG Ultra (99% @ 20u) and the new Carquest EP (99% @ 25) that use full synthetic media (and both are rated to 20K miles) are exceptions to that. It all depends on the media design. If you're actually going to run a filter for extended OCIs, use an extended use filter that has efficiency on the high end.
Side note info. I just noticed that Purolator took the ISO 4548-12 efficient note off the bottom of the page for the Boss. It use to say 99% >46u (after the M+H Pres was made aware of the Boss Spec Sheet info), so apparently Purolator is now not divulging efficiency info on thier low efficiency filters.
And they also never fixed the efficiency info for the PL30001 (the ONE) on the website to match the official Spec Sheet. And they show the bottom tier (red) Purolator L30001 at 99% @ 20u (same as the Purolator ONE) which I have a hard time believing.