Features:1. The keyless drill chuck with self-locking function breaks the traditional locking method, has a strong clamping force, and more effectively prevents the loosening of the workpiece2. Drill chuck with unique thrust bearing can easily convert manually applied torque into greater clamping force3. 1/2-20UNF drill chuck has a good metal texture and a comfortable coating surface4. Self-locking chuck suitable for 1/2-20UNF handle adapter5. Self-locking drill chuck suitable for electric drills, electric screwdrivers, etcSpecification:Clamping range: 2-13mm (1/16"-1/2")Connection size: 1/2-20UNFPackage list:1 * Drill Chuck