Setting the standard for power and value, the HMF Performance Series has been track tested with over a decade of championships. The specially designed, unrestricted core provides maximum flow and allows the exhaust to increase horse power and torque evenly throughout the entire power curve. The trademark to the HMF Performance Series is the exhausts sound. With a deep, aggressive sound, youll typically see a 2 - 10 dB increase from the stock exhaust system. Designed for 4-stroke sport quads. T-6061 aerospace grade aluminum canister. TIG welded aluminum brackets. Heavy-duty stainless steel rivets. Two-piece billet end caps that accept a USFS-approved spark arrestor and the exclusive HMF quick-change low dB Quiet Core. Packed with Bristol Core brand pillow packing. Two-year manufacturers warranty. Aluminum brushed finish. Hardware included. Sold individually. Includes installation instructions. Manufactured in the U.S.A. Equal Power: The Performance Series distributes power evenly throughout the entire RPM range. 2 - 10 dB Increase: Depending on the model, you can expect a 2 - 10 dB increase over stock. Unrestricted Core: The Performance Series uses a 2-1/8" non-restrictive core for maximum flow. Less Weight: The exhaust shell is made of T6061 Aluminum that weighs substantially less than stock.