Stainless Works Catback V6814300S 2-1/2" Mandrel bent Stainless Steel, Fits Factory Manifolds 1968-72 Corvette Exhaust system - big block-auto trans. CNC Mandrel Bent 2 1/2" 18 gauge 304 Stainless Steel. Designed to replace factory system and connect to factory correct manifolds Exhaust System