Keyless chuck finger-tightens for easy bit changes. Quick-change SDS-Plus/Hex/Square female adapter for electric hammer. Instantly convert impact driver to hold non-quick change drill & driver bits. Greater clamping force, effectively preventing drill bits loose off, more reliable. locking function, break through the traditional method of locking with ratchet, after locking piece of installation in the set, locking the perimeter longer, more effectively prevent easily in the work, make the clamp are more reliable when clamping tools. Specification: Type: Quick Clamp Clamping Range: 2-13 mm(1/16-1/2 Inch) Connection Sizes:1/2-20 UNF Applicable Scope: Suitable for the hand electric drill Material:Metal colour:Black + Silver Package Contents: 1 set x Adaptor Hardware Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/