#1 Square Recess Power Bit, 3-1/2 In.

#1 Square Recess 3-1/2" Power Bit, Shock Resistant Tool Steel For Maximum Durability, Hardened Core For Extra Strength & Long Life Heat Treated To Resist Breakage & Wear, For Driving Screws In A Variety Of Materials, Screw Type: 2, 3, 4.