3pc Wobble Power Extension Bar Bits for 1/4", 3/8", & 1/2" Drive Sockets - 1/4" Hex Shank Productivity-enhancing extension bar bits that let you use sockets with power drill or impact driver Unique anvil design allows slight socket 'wobble' for easier placement on nuts/bolts in tight fits No loss of driving power or fit; spring-loaded steel ball bearing keeps socket in place 2-1/2" bars for 1/4, 3/8 & 1/2" drive sockets; heat-treated & hardened steel, mirror chrome finish 1/4" hex shank with quick-change fits power drills, impact drivers and quick-change adapters