Bolt, Nut, Customized Fastener manufacturer / supplier in China, offering API 20e SL-1 Carbon Steel Steel En10204 3.1 Nace Mr0175 Ifi-115-2002 Black Oxide A193 B7 12 Point Hex Flange Bolt, Grade10.9 Black Oxide PTFE HDG ASTM A193 B7 Carbon Steel Ifi-115-2002 Hot DIP Galvanized 12 Point Hex Flange Bolt for Oil&Gas Industry, Ifi-115-2002 Grade10.9 Black Oxide PTFE ASTM A193 B7 Carbon Steel 12 Point Hex Flange Bolt for Oil&Gas Industry and so on.