Some vehicles are equipped with two catalysts due to their dual pipe assembly. The Secondary Catalyst Bypass pipe removes the secondary catalyst to improve gas flow and reduce restrictions caused by catalysts within the exhaust system. - Removes the secondary catalyst for improved gas flow - Reduces exhaust system restrictions - Designed for vehicles with dual pipe assemblies Specifications: - Pipe Diameter: 69.85 - Race Product: Yes - EMarked: No Kit comes with: - MSMZ68: LH Secondary Catalyst Bypass Pipe - MSMZ68 - MSMZ69: RH Secondary Catalyst Bypass Pipe - MSMZ69 - MSMZ71: Adaptor Pipe (OE cats to secondary cat bypass pipes) - MSMZ71 Vehicle Compatibility: - 2007-2011 Mercedes C-Class C63 AMG - 2007-2011 Mercedes C-Class Coupe 63 AMG