Khrome Werks 4-1/2" HP-Plus® Slip-On Mufflers - Chrome Edge780692126 Product Description These mufflers have been dyno tested and show a 12% increase in torque and 7% increase in power 4 1 2" 16 gauge muffler body Engineered for performance, style and sound Produce the Khrome Werks signature, authoritative tone without annoying high frequency noises Absorptive baffle covered with stainless steel mat and high temp fiberglass Improved torque and horsepower from the hit of the throttle Billet aluminum tips can