How to distinguish between good and bad air filters.

Filter precision, dust hold capacity and flow resistance are the import factor to determine the automotive air filters is good or not. these factors need testing instrument to test, except this we also can distinguish between good and bad air filters from appearance.

1.      Look the filter paper. Good paper is neat, smooth, waterproof . the pleat is uniform and compact. Paper with high stiffness.

For the bad paper, the color is not consistent. Paper with fluff ,don’t waterproof or water-resistant performance is poor, when in humid conditions in paper easy to be broken then the air filter lost it’s filter using.

2.      Look at the polyurethane. The good one adopt the polyurethane foam. No smell, comfortable hardness, with good elasticity and flexility.

The bad one with peculiar smell, when you fold the air filter element, the air filter with good polyurethane soon return to the original position and shape after the release, the bad one with poor quality PU will have obvious trace in the middle of filter or even crack because of the folding.