S&S CYCLE 4-1/2" MK45 Performance Mufflers - Black with Black Thruster 550-0621 Tires Mk45 4-1/2" Touring Mufflers are

Mk45 4-1/2" Touring Mufflers are the result of decades of riding

000" pistons for front and rear

Huge displacement increase means huge power increase

Piston Kit

Close tolerances for low leak down rates

S&S CYCLE 4-1/2" MK45 Performance Mufflers - Black with Black Thruster 550-0621 Tires Mk45 4-1/2" Touring Mufflers are4 1 2" MK45 Performance Mufflers Black with Black Thruster Mk45 4 1 2" Touring Mufflers are the result of decades of riding, racing and tuning, Combines both a stainless steel baffle and RaceTEX cartridge packing, Create a deep rumble and improved horsepower and torque, all while adding a unique look with styled aluminum endcaps, Includes removable dB reducer, Made in U. S. A., Not for Trike applications.