... Steel Twist Nail Nail body is twisted , head for round flat , Bottom for pointed bottom .Applicable to some very strong the ... options,Material:Iron, carbon steel, stainless steel, Q195,Q235.Head type: flat, round flat, oval, headless...Shank type: smooth ... spiral, Annular...Surface treatment: polished,black, HDG, ZP,YZP...Head diameter: 2mm~6mmShank diameter:1.5mm~6mmLength: 10mm~600mmStrength: HRC48 ...