S&S Cycle SS550-0990 GNX 4.5" Slip-On Mufflers Black w/Black End Caps for Touring 17-UpThe M8 engine is a powerhouse, but a low idle combined with a plugged up exhaust conspire to mute the true sounds of freedom that this machine was designed to emit. Not to worry, S&S have created the GNX slip ons with one thing in mind and thats belting out the flag waving, eagle flying song of the American v twin. Combining a 4. 5" shell with a tuned baffle and race inspired tip, the GNX lets the sound and power flow out of the M8. Wait, you only