... GB, ASTM, BS, JIS square pipe1.Item: Square hollow section, square pipe, square tube2.Standard: GB, ASTM ... , WT: 0.6mm-12mm 1. Commodity specificationsSquare hollow section2. Process methodCold drown, high frequency welded3. ... the supply of ERW pipe, seamless steel pipe, hollow section, galvanized steel coins, steel plate, stc ... you have any other questions, pls email us, we will be very glad to reply ...