The Mouser works by electrocution - see image below to see the physical configuration of the interior "floor" of the Mouser. Notice the metal plate in the center and the "C"-shaped metal plate surrounding it. These form the positive and negative terminals of a circuit. When the two plates are connected (by teeny tiny mice feet,) the Mouser detects the connection and starts passing electricity, which will pass through whatever is connecting the two plates. The electricity knocks out mice almost instantaneously, and it will continue to zap for a couple of minutes to make sure the deed is done. After it is done zapping, it will send a signal to the Z-Wave controller.
Inside the Mouser