All of our Street Legal crossovers utilize our small, but mighty, 5.0 litre ODBC compliant, catalytic converters. They out-flow most performance mufflers and weigh a mere 2.5 lbs. These are designed specifically to give your Mustang a major wake-up call in both sound and performance. The modular design of these x-pipes allow for conversion from off-road to street-leal and back to off-road with optional cat-delete pipes. Our Catalytic Converter X-pipes will pass emissions inspections in most states. Check your local and state regulations for installation and usage guidelines. Gain 8-12 HP and a unique sound!