To go along with duodeluxe, with a cheap bypass valve, that means on cool morning when you throttle up an engine, unfiltered oil is getting by the filter and headed for expensive engine parts, also with incorrect micron rating on filter media, the "Big Chunks" are being stopped, but the little ones make it through.
I have seen large diesel engines destroyed within a few weeks using aftermarket air filters in extreme conditions.
You can buy a lot of air filters for $12,000 plus labor and down time.