Gibson Performance 617009-B Cat-Back Dual Exhaust System Fits 15-21 ChallengerExhaust System Kit Cat Back Dual Exhaust System Cat Back Dual Exhaust System; Stainless 2. 5 in. Tubing; 4 in. Black Ceramic Round Slash Cut Double Wall Tip; Exit Straight Out Back; SPECIFICATIONS: Exhaust Type: Single Exit Position: Rear Exit Style: Straight Inlet Inside Diameter: 2. 500 in. Material: Stainless Steel Muffler Type: Chambered Outlet Outside Diameter: 2. 500 in. System Type: Cat Back Tail Pipe Diameter: 2. 500 in. Tail Pipe Material: