Re:What BOV is this?
 

How would it let in tuns of crap if it kinda like a sponge.Ive never used one its just that it doesnt seem physically possible.

Re:What BOV is this?
 

i'd say they work fine, the real HKS one has a finer foam on the iside of the coarser foam to make it catch a little more, the off-brand HKS "style" ones are probably pieces of ---- though.