Designed to rotate the crankshaft on heavy-duty Detroit Diesel and Mercedes Benz truck applicationsCorrosion-resistant and durable steel construction for strength and durabilityServices Detroit Diesel DD13 DD15 DD16 and Mercedes Benz Actros Models MBE4000 MBE900, Atego, Man 5, 6, 8-cylinder engines - D25/28Use with a 19mm Hex drive or 1/2" Square driveConstructed of carbon steel and high-quality alloy structural steel for strength and wear resistance