Features: This is a WiFi USB siren alarm with temperature and humidity sensor. With multiple ringtones for selection, high sensitivity and fast alarm speed. Environment friendly materials, without smell, radiation or harm. Two power supply ways, you can use mini USB or the backup CR123A battery. 90dB alarm sound, allows you to hear the alert from anywhere in your home. Mini and compact appearance, reasonable size design, brings you convenience and enjoyment. Stable performance, strong practicality and easy installation. Specification: Condition: 100% Brand New Material: ABS plastic Color: White Power Supply: Mini USB, 5V-1A Backup Power Supply: 2 x CR123A (Not Included) Sound Intensity: 90 dB Wireless Type: 2.4GHz Protocol: IEEE 802.11b/g/n Wireless Range: Approx. 45m/147.6ft Operating Temperature: 0℃~50℃ (32°F~122°F) Free App: Tuyasmart or Smart Life Support Systems: For Android and For IOS Package Size: approx. 9.5x 8.5 x 5cm/3.7 x 3.3 x 2in Package List: 1 x Siren Alarm 1 x Pack of Screw 1 x User Manual 1 x USB Line 1 x Glue Note: Please note that the old and new type of the product will be sent randomly, and make sure you will not mind before ordering. .