Kooks Custom Headers 11413500 Catted H-Pipe Fits 11-14 MustangExhaust Crossover Pipe Catted H Pipe Catted H Pipe; 3 in. x 2 3 4 in. Outlet; Must Be Use w Kooks Headers; SPECIFICATIONS: Clamps Included: Yes Flanged Inlet: Yes Inlet Inside Diameter: 3. 000 in. Material: 304 Stainless Outlet Quantity: 2 Shape: H Pipe Tube Diameter: 3. 000 in. WARNING CA Proposition 65: Yes WARNING CA Proposition 65 Message: WARNING: This product can expose you to chemicals including Chromium and Nickel which are known to the State