1what it does
Placed down, it puffs out colored balloons forever with no fuel and no upkeep. They drift upward, bump along anything solid above them, and fade out after a few seconds. Nothing about them is functional. They will not pop on spikes, they trigger nothing, and they never build up enough to block your view.
wiring it
The switchable part is what makes it usable in a real build. Run it off a pressure plate at the door and it only runs while somebody is in the room, instead of spitting balloons at an empty house all night. Boxing it under a low ceiling makes them pool and linger, which looks a lot better than letting them escape straight up.