Scooterx Torque Box Performance Pipe Exhaust System for Gas Scooters, Evo, X-treme, Scooterx and More Increases top speed 4-7mph, Increases overall torque CNC Milled from 6061 Billet Aluminum, Made in USA! Has a great sound thats louder and beefier than stock Increases RPM's 400-600 depending on engine and mods Larger exhaust port to allow more air flow for way more power!