Federal Signals SST3-MV is an electronic siren capable of producing three different high decibel tones from the same unit. The Model SST3-MV features internal amplification and the circuitry required to produce three different tones. The user activates each tone (wail yelp or horn) with dry contacts from a remote point. The SST3-MV operates on 24VDC 120VAC or 240VAC. The NEMA 3R housing is molded from impact resistant ASA (acrylic-styrene-acrylonitrile) plastic making it resistant to ultra-violet light and idea for indoor or outdoor use. The Omni-directional swivel mount system allows the output to be pointed anywhere within a 360 degree half-sphere. Typical applications include emergency warning start and dismissal fire alarm general alarm and evacuation.