1/16-1/2" (2-13mm) 3/8"-24 Thread Keyless Drilling Drill Chuck UNF Thread Mount Thread keyless drilling chuck Range: 1/16-1/2" ( 2-13mm) ; Threaded Mount: 3/8"-24 The locking system designed for the protection from loose-grip in the drilling operation ; Precision machining and careful tested ; Easily Closed by hand; Does not slip ; Hardened and ground and accurately made The "quick" locking mechanism maintains the grip and avoids possible slip of the tool during hammer drilling or while screwing/unscrewing. Quantity: 1 ; Shipping weight: 10 OUNCE ;Ergonomically designed with plastic sleeves that eliminate the possibility of rust