Bluetooth Wireless Connectivity: The wireless temperature sensor uses a high-end Bluetooth 5.0 chip. Easily monitor temperature and humidity data on CozyTime App via Bluetooth. Detecting range is up to 30m (98ft) without obstructions. Free Data Storage And Export: Store a set of data in 5 minutes intervals, support up to 100 days data storage. One smart device can be connected up to unlimited number of temperature sensors simultaneously. High Accurate Monitor: Temp. range: -20~80(-4~176) , Humidity range: 0-99%RH. Up to 1s responsive speed always shows you the latest readings. Smart Alert Function: Set preset temp and humidity ranges, and receive an app alert immediately whenever levels fall out of that range, which helps you react faster to sudden changes in your greenhouse. Pocket-sized Design: With a compact and lightweight design. Perfect for monitoring home, pets, refrigerators, freezers, walk-in cooler, wine cellars, etc. CR2032 battery lifespan is about 1 year and can be replaced by yourself. Wireless Range: 30m (98ft) Humidity Range: 0-100%RH Humidity Accuracy: 3%RH Temp. Range: -20~80C/-4~140 Temp. Accuracy: 0.3C/0.54 Battery Model: CR2032 Historical Data: 100 days Smart Alarm: YES Magnetic Back: Yes Material: plastic colour: C-White + Green Package Contents: 2 x Temperature Sensor CT01 1 x CR2032 batteries 1 x English instructions