Atoplee 4pcs Drill Chuck Wrench for Electric Drill Clamping Tool [Chuck Diameter:20mm/10mm/13mm/16mm] Drill chuck wrench for electric drill clamping tool. Used for controlling tightness of looseness of electric drill clamping tool. Chuck Diameter:001:20mm, 002:10mm, 003:13mm, 004:16mm Outer Diameter of Gear:001:25mm/002:13mm/003:18.5mm/004:21.5mm Can be used in hammer or drilling mode,very durable, comfortable to grip. Used for controlling tightness of looseness of electric drill clamping tool. Chuck Diameter: 001:20mm/002:10mm/003:13mm/004:16mm Teeth Quantity:001:11pcs/002:11pcs/003:12pcs/004:11pcs Outer Diameter of Gear:001:25mm/002:13mm/003:18.5mm/004:21.5mm 001:9mm 002:6mm 003:6mm 004:8mm 001:approx 111g 002:approx 21g 003:approx 34g 004:approx 63g Package Included:4x Drill Chuck Key