Features: Smart chip, low power consumption, high precision, stable performance, respond quickly.  0-30% oxygen content detection, with sound, light and vibration alarm.  Measure the environment temperature, with 2 temperature units (℃ and ℉).  The portable oxygen detector is a kind of essential safety instrument which can continuously detect the oxygen concentration in the working environment. It is suitable for explosion-proof, toxic gas leakage, underground pipelines or underground mines and other places.  This instrument is a natural diffusion method for detecting gas concentration, using high performance electrochemical sensor, with excellent sensitivity and excellent repeatability.  The instrument adopts embedded micro control technology, simple operation, complete functions, high reliability.  This O2 detector is applicable to the concentration of oxygen in the ambient air detection, are widely used in metallurgy, power plant, chemical, mine, tunnel, underground pipelines and other places, effective prevention of hypoxia and oxygen poisoning.   Specification: Sensor: Electrochemical principle;  Test Gases: Oxygen concentration (O2);  Temperature Measurement: Ambient temperature;  Display Unit: O2: %VOL;  Temperature: ℃/℉;  Measurement Range: O2: 0 ～ 30%VOL;  Temperature: -15～50℃ / 5～122℉;  Resolution: O2: 0.1%;  Temperature: 0.1℃ / 0.1℉;  Accuracy: O2: ±3.0%FS;  Temperature: ±1.5℃;  Response Time: T90<15s;  Alarm: Sound and light vibration alarm;  Alarm Point: low alarm point 19.5%VOL, high alarm point 23.5%VOL;  Battery Type: 1 * 3.7V 1200mAh rechargeable lithium battery;  Operating Temperature: -15～50℃ / 5～122℉;  Operation Humidity: 15%～95%RH (non condensation);  Storage Case Size: 240 * 198 * 55mm / 9.45 * 7.79 * 2.16in;  Item Size: Approx. 180 * 70 * 30mm / 7.09 * 2.76 * 1.18in;  Item Weight: Approx. 209g / 7.39oz;  Package Weight: Approx. 677g / 23.88oz;  Package Size: Approx. 24.5 * 20 * 5.5cm / 9.65 * 7.88 * 2.17in;   Package List: 1 * O2 Detector;  1 * USB Cable;  1 * Storage Case;  1 * User Manual (Manual)