stainless steel exhaust pipe/tube 1.Appliccation:exhaust system 2.Perforated round hole stainless steel exhaust pipe/tube description: 1) Standard: JIS, AISI, ASTM, DIN2) Outside ... ,321,316,316L,4305) Surface: mirror polish, satin finish6) Application: exhaust system7) Perforated round hole8) Packing:as customer's requestion