im guessing the real cheap ones are set to work as the stock ones are, and they only stay held in by means of the lid.. they have no hose clamp/adapterplate.. so youd probaly have to remove your proflow afapter plate to get it to fit on, they dont seal good they just butt up against the front of the airbox, very shitty, whatever you do, get one that hose clamps on to an adapterplate |