suppplying square hollow pipe: Hengji Steel suppplying square hollow pipe :1.OD: 15*15mm-400*400mm, WT: 0. ... , JIS square pipe1.Item: Square hollow section, square pipe, square tube2.Standard: GB, ASTM, BS, JIS, ... Q235, Q345B, X42, Gr. B4.Specification: OD: 15*15mm-400*400mm, WT: 0.6mm-12mm 1. ... are specialized in the supply of ERW pipe, seamless steel pipe, hollow section, galvanized steel coins, steel ...