S&S GNX Slip-On Mufflers For Harley Touring The M8 engine has various pros versus the prior Twin Cam engine, however there are a few cons that have surfaced such as the low idle note combined with a choked stock exhaust system that doesn't allow the sound most are used to. S&S Cycle has heard the customers and created the GNX slip-on mufflers. This pair of mufflers combine a 4.5 muffler body equipped with a tuned baffle and finished off with their race inspired end cap, letting the sound and power flow as it should. Features: Give your bike a true V-Twin rumble without a full system Premium Fit, Finish, Sound and Power New, unique louvered baffle delivers a rowdier tone, even with stock headpipes S&S Racing heritage styled endcap in new tuxedo black finish SAE J2825 Sound Level Compliant (with included dB reducer installed) Relieved for shocks up to 13.5 50-State legal Made in the USA