Valve Cover Breather Clamp On 5/16"(8mm) Id Neck Chrome Top Red Element (Ref K&N 62-2470). The filter is 30mm tall, 35mm in outside diameter with a 8mm (5/16 inch) flange which is designed to clamp directly on to metal or plastic tubing. This air filter is constructed with non-woven synthetic filter media so it can be cleaned and reused repeatedly.