Cold forged steel body heat treated for exceptional wear resistance. • Precision ground needle roller bearing with high chromium steel axle for long life and minimal friction. • Cold forged extra long piston, precision ground and fitted for controlled leak down and pump up. • High flow disc style quick reacting check valve for better reaction at higher RPM. • Precision oil metering assuring proper oiling to the rocker arms without sacrificing oil pressure. • Proprietary tie-bar system • All hydraulic lifters are available with short travel, variable duration lift, and axle oiling features.