Abstract: The present invention relates to an all-purpose, pneumatic powered signaling device including a first component capable of transmitting signals above water and a second component capable of transmitting a signal beneath the water. The first component includes a pneumatic air horn and the second component a diaphragm and piston. A button actuator is selectively depressed to create a flow passageway from a source of compressed air to the first and second components. A selector switch is selectively adjustable to allow a stream of compressed air flowing through the passageway to enter either the first or the second component and transmit a signal above or below the water.