Materials: High quality SUS304Certificates: ISO/TS 16949:2009 Warranty period:2 yearsFeatures:Stainless steel Flex section has an outside S/S braid and a convoluted tube and then another S/S braid on the inside for added for strength. 1) Isolate vibration generated by your vehicle's engine, thereby relieve stress on the exhaust system.2) Reduce premature cracking of manifolds and downpipes and help extend the life of other components.3) Feature an internal stainless steel interlock liner that facilitates smooth flow of high temperature exhaust gases. Specifications:BEL:Bellow+CapB-O/B:Bellow+Cap+Outer-BraidB-I/B:Bellow+Cap+Outer-Braid+Inner-BraidB-I/L:Bellow+Cap+Outer-Braid+Interlock