Power screwdriving bit is cryo-temp hardened for longer tip life. 1/4" hex shank fits all standard bit holders and hand-held drivers. ACR ribs on bit tip reduce cam-out. Special torsion zone reduces bit slippage and fracture. Precision formed tip for proper fit. Carded. Size: Phillips #1 Length: 2 In. Shank Diameter: 1/4 In.