Details1/4 Valve cover stud holes. Commonly used on current Top fuel heads SCE Gaskets severe duty steel core material with compressibility for good sealing and enhanced lateral rigidity to prevent blowouts under high pressures. These gaskets are so effective that they are accepted by NHRA for supercharged nitro and alcohol applications. Recommended for cast valve covers or sheet metal covers and pans with billet flanges. Sold in pairs. NHRA Legal YES Steel Core YES Reusable YES If you need packages of 10 or more please call.