ROLLER CAM BUTTON; CHRYSLER HEMIROLLER CAM BUTTON; CHRYSLER HEMIHolds The Cam Back1 Year Limited WarrantyAll roller cam lobes are ground flat instead of tapered, like hydraulic or solid cams, it is necessary to provide some means of holding the cam back to the rear of the engine. These cam buttons from COMP Cams ride between the front of the timing gear and the back of the front cover and can be shimmed for proper endplay of the cam. COMP Cams makes solid nylon buttons and roller bearing thrust buttons for the ultimate in performance.CamThrustButton