Air Cut Off Valve Kit. The All Balls air cut off valve kit contains all the necessary components to rebuild your air cut off valve circuit. Kit includes: Diaphragm and spring, O-rings (if needed) and screws. Sold as a kit. Notes: Order one (1) kit per motorcycle, kits include all needed individual parts for multiple carb applications if applicable. Kit contents will vary based on fitment. Models with multiple carburetors include components to repair all carburetors.