J3516A. This high quality Keyed Drill Chuck is made of heavy duty steel with 1/2" - 20 UNF Mount. It fits almost every brand's drill motor. Compatibility details are provided below. Compatible With: Features: Plated body provides a rust resistant finish 1/2" - 20 UNF Mount with collar for additional torque Fits most major tool brands Heavy duty 5/8" keyed steel chuck Specifications: Maximum capacity(in): 5/8" Minimum Capacity(in): 0.12" Mount: 1/2"-20UNF Runout(in): 0.013" Sleeve Diameter (in): 1.95" has been a factory direct distributor of power tools, accessories, fittings and shop machinery since 1986.