The SpectrAlert Advance series of mini-horn sounders are designed to simplify installations to provide primary and secondary signaling for fire and security applications. The MHR and MHW mini-horns operate at 12V and 24V and are ideal for hotel, motel or residential fire system applications, where a smaller notification device is desired. The mini-horns offer high and low volume settings, and temporal or non-temporal tones. The horns can be mounted to single gang back boxes for aesthetically sensitive applications. Synchronization is also provided when using the MDL module. The MHR and MHW mini-horns can operate between 32 and 120 degrees Fahrenheit from a regulated DC or full-wave rectified, unfiltered power supply. They are listed to Underwriter’s Laboratories Standard UL 464 for fire protective signaling systems.