1,1/4"hexagon screw driver bits,screwdriver bits 2.material:S2 STEEL, ... STEEL 3.surface:sand blast or black 1/4"hexagon screw driver bits,screwdriver bitsSpecifications 1. Material: S2, Cr-V ... be required by customers 4.Type:double head, non-magnetic and magnetic 5.Head types:PH,PZ,T,and so on ... 6.Special heat-treated 7.Quality guarante and lifetime more longerThe hex screw ...