( 2 ) 4 WAY Chuck Key Large & Small 1/2"-3/4" & 1/4"-1/2" Power Drill Bits Small Key Fits: 1/4 to 1/2 Chucks. Large Key Fits: 1/2 to 3/4 Chucks . 100% quality and 4 Way Drill Chuck key Used For most electric drills and power tools Polishing surface treatment