... Q345, 20#, ST37, ST44, ST52, ASTM A53, ASTM A106 Rectangular hollow section:1.Item: square pipe2.Standard: GB, ASTM, BS, JIS, ... 400mm, WT: 0.6mm-12mm1. Commodity specificationsSquare hollow section2. Process methodCold drown, high frequency welded3. MaterialQ195---Q2354. Size a. ... meet customers' needs with the satisfied service and competitive quality.In case you have any other questions, pls email ...