The intelligent precise oxygen detector use electri-chemical type gas sensor to measure the gas, can quickly response to oxygen gas, sound and light alarm level can be set manually. Great tool for home, agriculture, chemmical industry, general industries. Features: PROFESSIONAL OXYGEN DETECTOR -- Portable oxygen(O2) gas detector, measure range 0-25% oxygen content. Adopt electri-chemical type gas sensor to measure, this oxygen detector sensor with stable performance and  high accuracy. ADJUSTABLE ALARM -- Sound and light dual-alarm when O2 gas concentration reaches the level of the alarm.  And the alarm value can be customized according to users demands. BACKLIT LCD DISPLAY -- The gas meter is compact and lightweight, features a large LCD display with backlight, you can get the result from the screen at a glance, even in dark,easy to carry on and convenient for reading. USB RECHARGEABLE -- Come with a 3.7V rechargeable lithium battery, charging through micro USB interface, which can be powered by power adapter, power bank, etc.. WIDELY APPLICABLE -- The Oxygen detectorCs can be used in metallurgy, power plant, chemical, mine, tunnel, underground pipelines and other places, effective prevention of hypoxia and oxygen poisoning. Speicification: Color: Black + Blue Material: ABS Detecting Gas: Oxygen Voltage: AC100-240V, 50/60Hz Output: DC5V, 1000±50mA Measuring Range: 0~25% Resolution: 0.1% Basic Error: ≤ ±5% full scale Temperature: -10~50℃ Resolution: 0.1℃ Working Humidity: 1%RH~99%RH Response Time: ≤15S Recovery Time: ≤15S Alarm Mode: Acoustic and Light Auto Power Off: Mannual Selectable (10 mins no any key press down) Power Supply: 1 * 3.7V, 1000mAh rechargeable li-ion battery Screen Size: 4.4 * 5.3cm / 1.73 * 2.08in Item Size: 180*65*30mm / 7.09*2.56*1.18in Item Weight: 182g/6.42in Packing List: 1 * Smart Oxygen Detector 1 * USB Cable 1 * User Manual 1 * Carry Bag