" indicate the difficulty level for installing the product.The Dynojet jet kit includes everything you need to fine tune your ride for new exhaust, new air cleaner or both. Adjustable tapered needle and a rich selection of 4 main jets will cover a very broad array of confugurations. The kit also includes drill bit for removal of the Pilot Mixture Screw plug for optimal adjustment of the pilot circuit. All hardware (washers, clips etc) necessary for the fine tuning of your carb is included in this kit designed by DynoJet, the performance experts that build the Dynomometer machines used around the world.