Where's the documented proof that the FRAM Ultra is 100% efficient at 20 microns ?
Where's the documented proof that the WIX XP is 50% efficient at 20 microns ?
Let's get down to the nitty-gritty !
Where's the documented proof that the WIX XP is 50% efficient at 20 microns ?
Let's get down to the nitty-gritty !