Requires an Ethernet Tag Manager.

• Motion/door open-close logging and notification with angle (3D compass) based motion sensor
• Beep to help find missing items
• Temperature logging and notification with 0.125°C resolution temperature sensor (1°C error/noise in reading, after manual calibration; please choose products with higher grade temperature sensors for temperature monitoring)
• Logging interval programmable from 15 seconds to 4 hours.  
• Long wireless range allows placing inside most refrigerator/freezer to monitor temperature & door
• Out-of-range/back-in-range notification
• Unlimited storage of motion event data and logged temperature on cloud (can be deleted any time)
• Not optimized for usage in freezer, for detail see temperature Feature comparison matrix

Battery: Installed, CR2032 x 1 (replacement instructions, where to buy)
Supports PC/Mac through a web browser, app push notification: iOS 9.0 and above, Android 5 and above. Works with Amazon Alexa and Google Home.