The core function of the J-Model TOOB apparatus is effectively the same as the Craft TOOB. The key difference is the onboard controller and oxygen generator (normally sold and installed separately.) When a location is selected, simply install it into irrigation leads, set the exact D.O. level you want on the front-facing controller, then turn the switch to either "On" or "Auto". You can turn it off manually by simply switching said controller to "Off".