HKS’ high-performance Super Filters are a direct replacement for OE panel filters when a factory airbox is required or preferred. Super Filters feature the same 2-layer wet-type, polyurethane material as in the Super Mega Flow cold air induction kits. The filter element is bonded to a flexible nylon frame and offers a price-friendly performance alternative to a full intake system. This is an alternative to the K&N Air Filters for stock air boxes, which is required in Spec Miata's with 1.8L engines. The filter material is made of a foam, instead of paper like a K&N.