Linear WA105DBZ-1 - Z-Wave Sounder. Audible and visual indicator for alerts. Loud audible alarm > 105dB @1 meter. Integrated LED strobe. LED Status indicator. Tamper Switch. Low battery detection. Signal (frequency): 908.42 MHz. AC powered. Battery Back-up. Up to 100 feet between the wireless controller and/or the closest Z-Wave device. Operating temp: 5F-140F (-15C-60C). Working voltage: 6V. Dimensions: 4.6x3.0x1.6 in. (116x77x40mm)