... ,HL,200# polishing, 400 # polished 304 seamless tubeStainless steel is a production which not easy rust,acid resistance and corrosion resistance ... ,ST12,HJ58,HG60,DB685,16Mn,20G,65Mn,510l,ASTMA299,ASTMA515,ASTM A 572,ASTM A 709,ASTMA302,ASTMA537,API X52,API X 42 and ...