TEKTON 47776 1/2-Inch Drive by 21 mm Shallow Impact Socket, Cr-V, 6-Point Engineered for use with impact drivers High-torque, 6-point opening grips flat sides of fasteners, not corners, preventing round-off Shallow well allows socket to fit into tighter spaces Large, high-contrast size marking is permanently laser etched and easy to read, even in low light Made of premium chrome vanadium steel with a protective black phosphate finish