black welded square steel tube Material:Q195 Q235 St52 ... SGS,API Bright,Oiled, black welded square steel tube Specification:1. Outer diameter:15*15- ... :woven bag, wooden caseUsage:Mechanical & manufacture, Steel structure,Shipbuilding, BridgingMain market:Middle East, Africa, ... Industrial and Trading Co.,Ltd AmandaTel: 86-0315-2247360Fax: 86-0315-2247325Skype:amandawang08 black welded square steel tube