1、[High Sensitivity Sensor Probe] The oxygen content detector has a high sensitivity sensor probe, and 3 alarms of sound, light and vibration. 2、[Clear Display] High definition display, clear numbers, clear at a glance, which is easy to understand and read, to meet your various need. 3、[Simple To Use] This gas concentration analyzer is powered by 3 AAA batteries (battery not included) and is easy to use, so you can use it with confidence. 4、[High Accuracy] This oxygen content detector has accurate measurement results, short response time and stable performance. 5、[Widely Application] Widely used in many situations, such as petroleum, chemical, environmental protection, metallurgy and other industries and places. 1 x Oxygen Content Detector (Battery Not Included)1 x Manual   Item Type: Oxygen DetectorMaterial: ABSProduct Size: Approx. 120 x 65 x 25 mm / 4.7 x 2.6 x 1 inTest Gas: OxygenMeasuring Range: 0 ~ 25%VOLMeasurement Error: ±2%Resolution: 0.1%Warm Up Time: <10 secondsResponse Time: <15 secondsAmbient Temperature Measurement: -15~50℃Alarm Mode: Sound and light alarm, vibration alarmAlarm: Low concentration 19.5% volume yellow warning light flashingHigh concentration 23.5% volume red warning light flashing(Alarm concentration can also be set)Continuous Working Time: 6 hours (with slight changes in working status)Power Supply: 3 x AAA batteries (Battery Not Included)Sound Prompt: The higher the frequency of the sound, the higher the concentrationWeight: Approx. 170g / 6oz