The SE Series Speakers and Speaker Strobes feature high efficiency sound output with dual voltage 25/70 V capability and field selectable taps from 1/8 to 2 W. They are designed to provide a sleek, aesthetic appearance for emergency voice/alarm communications systems. All SE Series wall mount models mount to standard 4-inch x 2-1/8-inch electrical boxes w/ no extension ring required and incorporate a speaker mounting plate for faster installs. The grille cover snaps on so no mounting screws are visible. Attractive surface boxes are also available. These SE Multi-Candela ceiling appliances are part of the new family of ceiling mount strobe appliances that will also be available on strobes, horns and horn/strobes. Optional Extender (SPEXT) is for mounting to 4-inch backboxes w/ no extension ring. The SE Series Wall Mount Spkr Strobe models use low current draw strobes for wall mounted applications.