FMF SST Pipe A nice hit off the bottom then it comes alive in the mid range and outperforms everything else on the top end Dirt Rider Magazine Product of the Year Nickel plated for great looks and easy care Note: Some models require a special SST silencer with this pipe. The SST is FMF's top of the line 2-stroke exhaust pipe. Unique and trademarked via the SST module on the back and its chrome plating, the SST Exhaust system greatly improves the entire powerband. The SST was voted Product of the Year by Dirt Rider Magazine. The unique aspect of the SST is the patented shape of the exhaust system and its ability to increase horsepower through the use of sonic wave technology. The most noticeable part of the SST pipe is the various bulges and funnel shapes. The SST exhaust system changes the sonic waves, backpressures and exhaust gas temperatures that effect engine performance and throttle response. You get more power and better throttle response.