I found this info on Rumble Pack. Sounds good ?
"If you are looking for performance you have come to the right place. Sno-Stuff Rumble Pack Silencers continue to set new standards in the industry. All Rumble Packs are designed from the ground up with performance, quality and reliability as primary goals. In other words, we did our job so all you have to do is ride, and ride hard. Extensive dyno testing with the best equipment available insures accuracy and honesty that others can not match. We pride ourselves in making sure that the fit is pefect with no modifications to the belly pan necessary for installation. These silencers will give you an increase of 3 to 6 more horse power and reduce your weight from 7 to 9 lbs"
We didn't stop there either. The exclusive Rumble Pack internal design allows for stock like sound levels but with an exhaust note that is nothing like stock at all. After all, something this exceptional in performance, looks and quality should get noticed. No other silencer in production offers all these qualities at such an affordable price. You will not be disappointed. We are constantly adding new application so if you do not see your sled listed below, please call or visit our web site for up to date releases. Also dyno sheets can be provided for HP verification.
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