I picked up a K&N oil filter with some Pennzoil Platinum yesterday at advance auto parts. The guy at the store picked out the oil filter, so I wasn't able to inspect it until I got home. Well when looking down the hole to the bottom of the dome there is a place where (whatever they use to glue them together) got away from making a circle. Basically I was just unsure if the filter would still filter and if the oil would just pass through the "hole" if there is one. I will post a picture later today if I can get a photo of it. I'm probably over exaggerating it.