These mufflers have been dyno-tested and show a 12% increase in torque and 7% increase in power. 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 be rotated 360° at 90° increments; feature a high-temp powdercoated finish. 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.