... Rectangular hollow section:1.Item: square pipe2.Standard: GB, ASTM, BS, JIS, 3.Material: Q195, Q215, Q235, Q345B, X42, Gr. B4.Specification: ... OD: 15*15mm-400*400mm, WT: 0.6mm-12mm1. Commodity specificationsSquare hollow section2. Process methodCold drown, ... in the supply of ERW pipe, seamless steel pipe, hollow section, galvanized steel coins, steel plate, stc. We supply ...