Abstract: A portable water-resistant device for signaling vehicles such as a taxi is formed of a lightweight, transparent plastic and is battery powered. The signaling device is provided with a first housing, a second housing movable relative to the first housing, the first housing containing a light source and a power source and reflective symbols affixed to the outer face of the first housing. The light source is selectively electrically connectable to a power source, such as a battery, which is activated when the second housing moves relative to the first housing and contact points extending from battery terminals and protruding through the first housing meet with contact points of the second housing. Additionally, in another embodiment the signaling device may be provided with an outer movable housing having a switch, an inner housing containing a light source and a power source electrically connected to the switch, and reflective symbols on the outer face of the inner housing.