... are i made by iron. 2.surface:nickel. 3.weld nut standard: SO,DIN,AISI,JIS or as your reques Item ... NameWeld Nut Special FastenersBrand NameZhongguMaterialCarbon steel, stainless steel, zinc alloy, aluminumStandardDIN, ISO ... ~30daysPacking detailPlastic or poly bags ,then cartons and pallets. Weld Nut Special Fasteners