Offer Impact Bits Material: TaiWan S2 steel HRC: 59 ZHIDA Hardware.We are quality grade Screw Bits, Screwdriver, HSS drills, Nut Setter, Allen Key factory, Material original TaiWan, Export USA, UK, Germany, Brazil etc, OEM accept, Please keep our info and holp we can cooperate in the future. Any query and advice please kindly let us know, Waiting for your reply, Thanks.