... B), St37, St52, St42, S...Place of Origin: Tianjin China (Mainland) Secondary Or Not: Non-secondary Technique: cold ... Certification: ISO9001-2000 Produc t nameBlack annealed cold rolled steel pipe Wall Thickness0.7mm-20mmStandardStandard: BS 1387, BS 1139 ... .Payment termsT/T,L/CapplicationFluid pipe,structure pipe,gas pipe,hydraulic pipe,oil pipe,drill pipe,boiler pipeOthersWe can do special orders ...