... fittings Standard:GB /STM/ASME/JIS/DIN/EN.etc. stainless tubes and fittingsO.D.:38mm-325mmW.T.:1mm-110mmStandard:GB /STM/ ... steel tube: Grade: 304,304L,316,316L,316Ti,310s.312 stainless steel tube: Grade304, 304L, 316, 316L,316Ti, 310S, 321 ect ...