Wifi Temperature Sensor Tuya Thermometer Detector Digital Display Home Smart Life App Alert Freezer f74 1. Built- in Rechargeable battery : can be powered by external DC5V power supply or standby battery ( Please note : if you want to power the detector via backup battery ,Please open the back cover and switch on the detector ) . 2. Temperature Unit is optional (Centigrade or Fahrenheit ). 3. Check the History Record of temperature anytime. 5. Multi -User Supervision Supported : you can click to share the device to other users . 6. Buit in Buzzer : the Buzzer will sound when the detector was triggered. 7. APP :you can download it by searching for Tuya Smart or Smart Life, support android IOS smartphone. Plug Type :EU Plug,it applies to Indonesia, Germany, France, , Italy and so on. Voltage: AC100-240V Colour:As Shown Material:plastic Package Contents: 1 x Tuya WiFi Temperature Sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.