CO2 Injector has 1/4" female flare thread opening. Uses 16g Cartridges.Does not come with quick disconnect. Caution the cartridges contain liquid co2 that will dispense at over 600PSI. With that in mind, we suggest having the faucet open before pushing more co2 into a keg. Also, do not push the inject lever when not hooked up to a keg as you will put over 600PSI into a quick disconnect and will blow the top threads off.