Constructed from high-grade alloy steel, the TDC-625, Taper Mount Drill Chuck 1/8-5/8-Inch x JT-3 from JET® delivers rugged dependability for tough drilling jobs. The precision-made jaws are fitted to withstand 115 psi of torque without deformation for added reliability. The Jet hand drill chuck features heat-treated mechanics for superior surface hardening and improved wear resistance. A large chuck diameter accommodates drill shanks between 1/8 to 5/8-inch for maximum versatility. The Jet TDC-625 taper mount drill chuck meets the exacting standards of JIS specifications for superior fit and performance in a wide variety of equipment. Package includes a Jet keyed drill chuck with Jacobs JT-3 taper fit and hardened chuck key for easy use right out of the box.