... .Square PipesWT:13.7-610mm 3.Square Pipes:high quality and competitive price Q235 Black Square Steel ... with 7 slats4.according to the requirements of customersUsageMechanical & manufacture, Steel structure,Shipbuilding, Bridging ,Automobile chassisMain ... country and America ,AustraliaCountry of originChinaProductivity20,000 Metric Tons per Month stainless square steel pipe 304,,316,309l,321 ...