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). Temperature unit is optional (Centigrade or Fahrenheit). Check the history record of temperature anytime. Multi-user supervision supported: you can share the device with other users. Built-in buzzer: the buzzer will sound when the detector is triggered. APP: you can download it by searching for Tuya Smart or Smart Life; supports Android and iOS smartphones. Plug type: EU plug, applicable in Indonesia, Germany, France, Spain, Italy, and others. Voltage: AC100-240V Color: 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 to differ slightly from the actual product. Measurement allowed error is +/- 1-3 cm.