FMF Power Up Jet Kit for Yamaha YZ250F 2007 012620 FMF has teamed up with Dynojet to produce a kit that offers you a selection of jets and/or needles to get maximum horsepower out of your bike fitted with an FMF exhaust Includes easy to use instructions with diagrams and stepby-step procedures to help you get your jetting where it needs to be, no matter what elevation you ride at