4-1/2" 16-gauge muffler body. These mufflers have been dyno-tested and show a 12% increase in torque and 7% increase in power. Absorptive baffle wrapped with stainless steel mat and high-temp fiberglass. Engineered for performance, style, and sound. Produce the Khrome Werks signature authoritative tone without annoying high-frequency noises. Improved torque and horsepower from the hit of the throttle. Billet aluminum tips can be rotated 360° at 90° increments. Optional performance inserts boost low-end performance and enhance sound. Bolt-in optional inserts available that comply with SAE J2825 sound test with no appreciable loss of performance. Sold in pairs. Made in the U.S.A..