Useful air quality detector with quick response and high precision to test oxygen content in the air that surrounds you, and real-time display time, date, temperature and relative humidity. Features: 3.5-inch TFT HD Color Display: real-time display current time, date, oxygen, temperature and relative humidity. The screen has wide viewing angle that can reach 160, which is very easy to read. Data Logging Function: with up to 65,534 groups maximum storage management space, convenient for browsing the historical data saved by the system. Semiconductor Sensing Detection Technology: monitoring air quality in your surrounding with highly accuracy, real-time detect O2, temperature and humidity. Simple Stylish Appearance: the air quality monitor has small size and clean design, perfect fit for house with any decorative style. Free-standing style, no mounting required. Wide Applications: suitable for using in the car, bedroom, living room, office, classroom, library, etc. Specifications: Display: 3.5-inch TFT HD Color Display Data Storage: 65534 groups Power: Built in 3.7V 3000mAh lithium battery Input: 5V/1A Temperature Test Range: -9~55 Humidity Test Range: 0~100% O2 Test Range: 0~30% Working Environment: -9~55