Description 4508-16 Competition Cams Rocker Arm Nut For Use With Full Roller Tapered For Extra Strength In Locking Area Compatibility: Full Roller Rocker Arms Style: Polylock Length: 2 Inch Thread Size: 7/16 Inch-20 Body Diameter: 3/4 Inch Head Style: 8-Point Head Includes Set Screw: No Quantity: Set Of 16 Choose COMP Cams® for superior performance and reliability Benefit from tapered design for extra strength Backed by a limited 1-year warranty.