We have over 30 years experience building, and tuning skis. Over these years I have kept notes on what jetting we have used for specific set ups. We sell jettting kits, based on these notes. Each kit is for ONE carb. Kit includes genuine Mikuni parts. One Pilot Jet, One Main Jet, One Needle and Seat, and One Needle arm spring. We are in Southern WI, and at aprox 700 feet above sea level. I will say, NO two skis are exactly the same, your location, elevation, build, set up, etc all will make a difference. We make NO claims that these jetting numbers will be perfect for your ski, just a good starting point to tune from. Please give detailed specs on your build in the comments section when ordering. I need to know what ski, what engine, what carb, compression, what pipe, impeller, and elevation where you ride. PLEASE email with questions before ordering. Thank you