Socket Extension Adapter Bit Set 1/4" 3/8" 1/2" Hex Square Nut Driver Power Drill Impact 6Pcs 6-Piece power extension bar set 1/4", 3/8", 1/2", each with a 1/4 inch shank/driver 1/4" hex shaft fits all quick-change adapters & extensions, drill chucks Turn your power drill or impact driver into versatile high-speed nut driver Heat treated and sandblasted high quality charome vanadium steel for superior strength and durability Ball bearing for secure socket holding