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 percent Brand NewMaterial: ABS plasticColor: White Power Supply: Mini USB, 5V-1ABackup Power Supply: 2 x CR123A (Not Included)Sound Intensity: 90 dBWireless Type: 2.4GHzProtocol: IEEE 802.11b or g or n Wireless Range: Approx. 45m or 147.6ftOperating Temperature: 0-50 (32F-122F)Free App: Tuyasmart or Smart LifeSupport Systems: For Android and For IOSPackage Size: approx. 9.5x 8.5 x 5cm or 3.7 x 3.3 x 2inPackage List:1 x Siren Alarm1 x Pack of Screw1 x User Manual1 x USB Line1 x GlueNote:Please note that the old and new type of the product will be sent randomly, and make sure you will not mind before ordering..