Heavy-duty design for use on most professional quality corded and cordless drills. Keyless chuck reduces bit changeover time and eliminates lost keys while providing greater gripping power than keyed chucks. Tough nylon and die-cast zinc sleeve design. Precision ball bearing internal mechanism. Includes most commonly used hex and torque wrenches to remove existing chucks retaining screw. Carded. Chuck capacity 1/16 In. to 3/8 In., thread 3/8-24.