... steel couplingsBS DIN ANSI Standard Carbon Steel Mild Steel Couplings screwed half couplingMaterialCarbon steel, Stainless steel, Alloy and ... standard, American standard and DIN standard Kinds of mild steel couplings : bends, elbows ,tees, crosses, sockets, caps, backnuts, ... ,stainless steel ,alloy steel . Surface of mild steel couplings: cold galvanizing,hot galvanizing,and black Egdes: banded, beaded ...