This COMP Cams High Energyâ„¢ Steel Stud Mount Rocker Arm designed for 1967-78 Ford 6 cylinder 240-300 Applications features a 3/8" Stud diameter and 1.6 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„¢.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 Camshafts