Here's how it works: 1) Insert repair nozzle into puncture. 2) Open regulated air valve to achieve desired pressure. 3) Close valve and remove tool. Plug will hold air and seal puncture simultaneously. The kit also comes with an air hose just in case you need to add more CO2 or simply want to use the tool as an inflator.
Kit includes two threaded 16 gram CO2 cartridges. One cartridge fills 26 x 4.6 Fat Tire from 0-14psi and will inflate average tubeless mountain bike tire to over 50psi. Tool will work with all threaded 12-25 gram CO2 cartridges.