The XSpeed Performance Pipe Is The Only True Performance Exhaust Designed For The X Series 4 Stroke Pocket Bikes - We Have Models To Fit The X15 X18 X19 and X22 Pocket Bikes. The XSpeed Performance Exhaust Sounds Awesome And Performs Even Better. Your Bike Will Pull Harder Throughout The RPM Range And Rev Higher. The Silencer Is Similar In Design to Big Gun or White Bros Exhausts With Billet Ends And A Perforated Race Insert.