Oxygen excessive alarm buzzer sound (excessive alarm sound can be eliminated by pressing any key) + digital color change (alarm value default standard value), you can set 1%-30% alarm value. 2.8 inch LCD HD color display. Display the oxygen concentration and temperature and humidity values, the curve interface. Features: Data saving function (can store 100000 data), set timing storage, delete data, view historical data., Manufacturer: Akfldms