... My company long-term supply stainless steel products, including stainless steel seamless pipes,stainless steel bar and stainless steel sheet. The material ... steel pipeWelded steel pipeSurface treatmentPolishing or not The stainless steel barstandardASTM,GBmaterial201,202,301,304,316,316L, ... ,309S,310,310S,430,409specificationRound Square rectangle Stainless Steel Seamless Pipes & Tubes