4″ 4-Jaw Independent Plain Back Chuck ~ Made of high quality steel. ~ Hardened and ground. ~ 1 set of 4 M8 mounting screws included. ~ Reversible, individual, adjustable jaws. ~ Adjusting wrench supplied. ~ Maximum RPM is 4,800. ~ Designed to grip round and odd shaped work. Made of high quality steel. Reversible, individual, adjustable jaws. Adjusting wrench supplied. Hardened and ground.