High Accuracy Sensor - Built-in upgraded MEMS sensor, it updates once per second to provide more up-to-date and higher accuracy data. The temperature error can be up to 0.5(1), the humidity error can be up to 5%. Adopted 5.0 Bluetooth chip, the temperature sensor provides real-time wireless monitoring of temperature (-20-60) and humidity (0-100RH). Upgraded to 50m(164ft) connection distance (in open area). Wireless APP Control - The temperature sensor uploads data to the APP when connecting to it via Bluetooth. You can check the maximum and minimum values of temperature and humidity on the APP. A smart device can be connected to up to 100 temperature sensors at the same time and supports Android 4.3 or later, compatible with iphone 4s or later. Smart Alert Reminder - The data on the APP turns red and sends a message to your mobile phone to remind you and your family to know the temperature and humidity variation when the data exceeds your preset value. It can be used to monitor home, pets, refrigerators, freezers, walk-in coolers, wine cellars and greenhouses. Data Export for Storage - Wireless thermometer hygrometer records data every 10 seconds in the APP, which is up to 100 days in total. (Make sure your phone comes within reach of it at least once a day.) Available to download data in CSV format for free after registered account. Mini and Portable Design - Our wireless temperature and humidity sensor is smaller than others (1.5 x 1.5 x 0.62 inches) and built-in CR2477 battery, it is about 1.3 ounces per piece. Battery life is about 10 months. A hanging hole is designed for different placements as you like. Space-saving and practical. Please contact us if you have any problems with the item and our service, we will try our best to solve the problem.