SONOFF SNZB-02D 2.5 inch LCD Smart Sensor Real-Time Monitoring Linkage 1. Power supply: CR2450(3V) button cell battery is included 2. Wireless connection: Zigbee 3.0 3. Operating temperature: -9.9 - 60 degrees Celsius 4. Operating humidity: 5-95%RH (non-condensing) 5. Housing material: PC 6. Size: about 62.5 x 59.5 x 18.5mm 7. Description: only the sensor, does not include other items in the picture Features: 1. Built-in high-precision sensor 2. Large and clear display, easy to read 3. 5s fast refresh, Celsius Fahrenheit units can be switched 4. Up to half a year of cloud storage, you can query any time temperature and humidity data and support export files 5. When the temperature or humidity exceeds your set comfort level, your cell phone will receive timely alarm notification 6. Supports zigbee gateway using Zigbee3.0 protocol, compatible with most gateways 7. Coverage up to 120m400ft (ideal for unobstructed conditions), view data at any time