Push-in Valve Cover Breather Black Coated Polished Ball Milled Alloy,with Pcv Tube for Hose Connection, features an internal baffle to prevent oil splash and provide superior ventilation.Supplied with internal replaceable Pcv Valve. Designed for 1-1/4 inch breather holes, with a 1 inch outside diameter neck. Ideal for use in conjunction with the grommet part number 41901, this breather includes a replaceable internal foam insert. Manufactured using high quality materials, this breather cap’s Alloy construction ensures it performs as well as it looks.