Stainless steel exhaust system. Silent version is close to stock sound level. Internally has multiple baffles/chambers to reduce sound level. Great system if you don't ride over 65mph that often.
Standard is a blow through design for maximum flow/power.
Standard with optional removable silencer tip to reduce sound and create some back pressure. This works well for the 158-175cc engine package. You can drill out the aluminium silencer tip to adjust the sound level and back pressure to match your engine requirements.