JK 160-R8 High Torque / High Precision Keyless 16mm Chuck with shnakMfr #: 31416 Arbor is integrated into the internal socket of the drill chuck It makes impossible for the arbor and the drill chuck to become accidentally separated, providing a unit of greater rigidity and precision with Self tightening feature automatically increases gripping force proportional to increased torque to prevent tool shank slippage Right handed operation only 100 percent individually controlled to ensure not to exceed a maximum total