Abstract: A double interaction switch has a case in which a single block of contactors is controlled by two levers; namely, one monostable lever and one bistable lever. The bistable lever may be locked in one of its two stable positions. When the bistable lever is so locked, the monostable lever may be moved, and actuation of the bistable lever thereafter causes it to return to its unlocked position. When the monostable lever comes back to its rest position, with the bistable lever initially locked, the bistable lever comes back to its rest position. The bistable lever is lockable by means of a rod which may pivot under the action of a labyrinth, provided on the lever. The switch is suitable for use with "hands free" telephone receiver sets.