1.material: carbon steel. 2.surface: nickel plated. 3.standard:This nylon nuts are made based on DIN standard. Item NameHexagon Nylon Self-locking NutsBrand NameZhongguMaterialCarbon steel ;stainless steel,brass,ect.Surface TreatmentZinc, copper, tin, nickel, ect.It can be environmentally friendly as your request.StandardDIN, ISO,DIN,JIS, BSW, ANSI or as your requestAdvantageHigh quality ,low in ...