To use the adapter, push down on the metal knobs on the adapter box and carfully attach to battery compartment. Screw in, then connect the adapter jack to the adapter box. Next, plug in to a nearby wall outlet. And you're ready to play.
This works on most TV game controllers, execpt for Atari Paddle, Bass Angler Championship, TV Kids controllers, TeleStory, vMigo, some of the TV motion games, and all the deluxe controllers such as Big Buck Hunter Pro.
There was also Super Value Power Packs that contain GameKey-ready controller, GameKey, and power adapter.