Discribtion:short radius return Materia:304,304L,309S,310S,316,316L,321 ... ASTM A234 WPB, carbon steel, Low Alloy, stainless(only for flange)ConnectionButt-welding, forged fitting Surface treatmentBlack rust-proof ... oil, chemical industry, water conservancy, electric power, boiler, machinery, metallurgy, sanitary construction etc. QualityISO9001: ISO2008-Quality-System has been passed PackagingWooden ...