3/16'' - 3/4'' Heavy Duty 3JT KEYLESS Drill Chuck JT3 3/16'' - 3/4'' Heavy Duty 3JT KEYLESS Drill Chuck JT3 Taper mount: 3JT ; No chuck key required ; Length: 4 1/2'' Hardened steel; Solid steel body Specifically engineered for heavy-duty, tight tolerance production drilling; Ball bearing construction to improve gripping force and drilling accuracy Quantity: 1 ; Shipping weight: 4.2 LBS