Adapter Kit allows Borla(r) Cat-Back(tm) systems 140837 140837BC and 140837CF to be used on 202+1-2023 Mustang Mach 1 vehicles. Adapter Kit includes 2) 2.25" I.D. inlet x 2.75" I.D. outlet x 5" long adapters and 4) clamps. Each Adapter Kit is built from premium high-quality T-304 austenitic stainless steel superior to T-400 series knockoffs (such as 409) to give you the absolute best in performance and durability. Precision computer numerical control (CNC) manufacturing ensures an accurate fit. Best of all Borla(r) stands behind every system with a Million-Mile Warranty. Just what you'd expect from the worlds most experienced (and most winning) exhaust brand.