ScootsUSA 190-48-6836 Bintelli Havoc Stainless Performance Exhaust Bintelli Havoc Oval Stainless Steel Performance After-Market Exhaust for 150cc ZNEN R-X engine based scooters. Overall Length (muffler): 13.5 inches Overall Outer Diameter (muffler at widest point): 126mm (5 inches). NOTE: will only fit a Bintelli Havoc motorscooter.