The siren will warn everybody in the building by a loud sound and a flashing light about an alarm. This product is especially suited for security applications in combination with other Z-Wave devices such as door or windows sensors or motion detectors. The siren gives a loud sound and a flashing warning light, so everybody in the building will know immediately that an alarm has occurred. The noise level fo the siren is > 105 dB in range of 1 meter. The device can be configured to either use the strobe flash or the acoustic siren or both. A tamper switch protects the device from removal or manipulation if used in security applications. The device is mains powered but has a backup battery inside to remain in operation in case of a power outage.Attention: Power supply is not scope of delivery.