James Dean designed the JDJetting kits so that you don't have to be an expert to get professional high performance results! The James Dean custom jetting kit is designed to improve throttle response throughout the range by using specially made multi-taper needles. These are based on the most popular settings used by new generation MX and off-road riders around the globe and the results are impressive. Exceeds the performance of standard two-stroke and four-stroke jetting, and other factory needle options. You can't buy this level of performance from the O.E.M. factory or other aftermarket suppliers. JD's testing and research will provide the performance you need. Exceeds the performance of other standard factory needle options and technical support is provided. Low and high altitude custom designed triple-taper needles. Main jets included. Spare needle clip.