DIN 2509 double end studs [1]standards:DIN 835,DIN 938,DIN2509 [2]material:carbon Steel , Stainless steel [3]surface:zinc DIN 2509 double end studsWe also supply hex head bolt, heavy hex structural bolt,hex fit bolt,hex flange bolt,flat countersunk square neck bolts,cup head nid bolts,single-head bolt,double head bolt. DIN 2509 double end studs