Race-proven technology and designMulti-stepped header design for better flow and powerAnti-reversion louver technology, providing low-, mid- and high-end torque and increased horsepower over stockEqualized back pressure ensures solid response without sacrificing performanceDesign highlights half-megaphone/half-straight 4'' muffler with a 4'' billet end cap and heat shields that fit seamlessly over collector and primary tubeAvailable in black with black end capsIncludes 18 mm O2 sensor portsReplacement end caps available separately12-17 Dyna models require bung adapter kit PART #1861-1095