... Tools,Stainless steel needle drilling,Stainless steel screwdriver,Bone Drill,Screwdriver, Needle Drill, Medical bit, Profile drilling-mill forming stainless high speed ... to shape.SKH4C: (a kind of high speed steel, which does not rust at all.)(Hardening treatment: HRC60°±2°)This is ... Holder profile.SKH4B: (a kind of high speed steel, which does not rust at all.)(Hardening treatment: HRC58°±2°)This is ...