COMP Cams 813-1 Solid/Mechanical Lifter .842 inch diameter; 98g weight; 1.88 inch seat height Manufactured using the tightest tolerances in the industry Lifter crown is ground to a precise radius for proper break-in and guaranteed long life Oil metering band is milled to the correct depth to prevent too much oil from being delivered to the top of the motor for Small and Big Block Chevy, Single Piece