This nitrided COMP Cams High Energyâ„¢ Steel Stud Mount Rocker Arm designed for Chevy V8 265-400 Applications features a 3/8" Stud diameter and 1.5 ratio. High Energyâ„¢ Rockers help eliminate the noise and slop associated with older worn and high mileage stock Rocker arms. With a long slot for higher than stock lift Camshafts, these Rocker arms are an excellent replacement choice for engine rebuilds using either stock or High Energy Camshaftsâ„¢. This Rocker has been nitrided to increase surface hardness for improved initial and long-term wear characteristics. The nitriding process increases hardness by causing an infusion of nitrogen molecules into the material's surface. This improves both the lubricity and wear resistance of the material.Excellent replacement Rocker arms for engine rebuilds with a stock or High Energy Camshaftâ„¢Help to eliminate noise and slop associated with worn or high mileage stock Rocker armsInclude adjusting nuts and pivot balls where requiredFeature a long slot for higher than stock lift CamshaftsNitrided Rocker arms designed for higher spring pressures and hardened Pushrods