It is a handheld Oxygen Detector,equipped with advanced sensor technology,precisely measure the oxygen content in the environment within a wide range. it is portable,along with a comfortable hand grip, allows you to carry the Handheld Oxygen Detector wherever needed with ease. The simple and intuitive operation interface and clear button settings effortless for even novice users to get started. Just turn it on and measuring, with real-time display of oxygen concentration,temperature, humidity, enabling you to stay informed of the environmental conditions at all times. When the oxygen concentration is below the safety range you set, it sound an alarms to remind you to take corresponding safety measures. Display Method:LCD Screen Measuring Item:Oxygen (O2), Temperature, Humidity Detection Method for 02:Electrochemistry Concentration Unit for 02:%Vol 02 Measuring Range: 0-30.0% Vol Atmospheric Pressure:12.5 PSI 15.4 PS Sampling Time:1.5 Seconds Temperature Range:-10°C-50°C (14°F - 122°F) Storage Temperature:-10°C-60°C (14°F - 140°F) Relative Humidity:20%-85% (The product appearance and printed words depending on the batch, but this does not affect use) Color: As Shown Material: ABS Package Contents: 1 x Oxygen Detector O2 meter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.