Flowmaster 817413 Header-Back Pipe Kit Fits 59-64 Bel Air Biscayne ImpalaExhaust System Kit Header Back Pipe Kit Header Back Pipe Kit; Dual; Dual Side Exit Before Rear Wheel; Incl. 2. 5 in. Outlet; 409 Stainless Steel; SPECIFICATIONS: Color: Gray Exhaust Series: Pipes Only Exhaust Type: Dual Exit Position: Dual Side Exit Style: Turn Down Heat Shield Attached: No Inlet Inside Diameter: 2. 500 in. Material: Stainless Steel Outlet Outside Diameter: 2. 500 in. Single or Dual: Dual System Type: Pipe Tail Pipe Diameter: 2. 500