Dynojet Thunderslide Jet Kit For Harley Sportster 1200 Features: Revolutionary composite plastic slide provides unparalleled performance gains in both horsepower and mileage Unique set of lift holes moderate how the slide moves with respect to throttle position the faster the slide opens the quicker the throttle respons Kit also includes jets, needles, clip and other necessary parts for CV carbs Works well with stock or aftermarket air box and exhaust system