... 1- thick-wall welded stainless steel pipe 2-standard:ASTM,GB,DIN etc, 3-good feedback of clients details of the pipe:Specifications:wall thickness:STD ... , XS, XXS or >=XXS."STD" is a code for standard thickness series, "XS" is a code for thick ... thickness series,XXS is a code for extraordinarity thick thickness series.grade:304,304L,321 ...