Review on Engine Filter Washable Reusable 0644 by Chase Cooper

It's not hard to change the air filter on a 2017 Ford Diesel 6.7. The ejection cost is greater than KN. This filter doesn't have the foam rubber that the original filter has, which bothered me. I contacted KN and here is their response. Hello, Thank you for contacting customer service. The reason we don't cover this hole is so our air filter can take extra airflow and fouling is not an issue. The OEM air box is designed to let the engine's air filter through and keep it clean by "sort of" blocking the air intake. Our K&N air filter is washable, reusable and doesn't get thrown away like an OEM paper air filter, so we need more airflow, so we leave the opening wide open. We understand your concern and will share it with our R&D team. Hopefully we can find something to discuss this scenario in the air cleaner pack for our future customers. Thank you, K&N Customer Service and Technical Support.