screw driver bit Head types:PH, PZ, slot, Torx, square, hex, Torx hollow, Torx plus, tri-wing, etc.. Special heat-treated Product Name screw driver bitsBrand Namesun-alpsLength25-300MMSurface treatmentsandblasted, tin-coating, Cu-coating, Ni-coating, Cr-coating, Zn-coatingMaterial6150 ,8660 ,S2Hardress58-60Head typesPH, PZ, slot, Torx, square, hex, hex-plus, Z-spanner, Torx hollow, Torx plus, tri ...