*Essential power tool accessory for hand-held power & cordless drills, drill presses *One tool with 4 key sizes for tightening and loosening chuck *Key sizes #1, #2, #3 and #4 overs all 3/8" and most 1/2" chucks *Steel with baked enamel finish *Drill without properly tightened chuck is virtually worthless - always keep extra key on hand