4-1/2" MK45 Performance Mufflers - Black Thruster Breather Kit Components Close tolerances for low leak

Close tolerances for low leak down rates

Bolt-in camshaft for 103” engines with stock 8

Multiple large openings allow for easy access

Highly stable and long life

4-1/2" MK45 Performance Mufflers - Black Thruster Breather Kit Components Close tolerances for low leak4 1 2" MK45 Performance Mufflers 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 Removable dB reducer Made in U. S. A. Not for Trike applications