A. Air quality detectors are widely used in places such as homes, offices, enterprises, governments, and schools. B. The air quality detector is equipped with a 2.8 - inch LCD screen, which can directly and clearly display each item of air data, and at the same time provide average values, real - time values, and environmental suggestions to present the air quality. C. The easy - to - read numbers and alarm sound function can let users know whether the air is unsafe. This is a type - X dust detector with a built - in 1200 mAh rechargeable battery and a USB cable. The standby time can last for 4 - 6 hours. D. This air quality and formaldehyde detector has a built - in electronic sensor that can detect carbon dioxide (CO₂), formaldehyde (HCHO), volatile organic compounds (TVOC), and particulate matter (PM2.5/PM10) in the air. These detection data involve the detection of toluene, harmful chemicals, and pollutants in the air. E. Formaldehyde detectors are widely used in homes, offices, enterprises, governments, schools, and cars. They can detect air problems at times to ensure the health of family members or employees. The mildew - proof air pollution detector equipped with a liquid - crystal color digital display can provide an average value for each item of data because the long - term real - time data is unstable. F. Specifications - Air quality and formaldehyde detector - Detection error: less than 15% - Formaldehyde detection range: 0.000 - 1.999 mg/m³ - TVOC detection range: 0.000 - 1.999 mg/m³ - PM1.0/PM2.5/PM10 detection range: 0 - 999 μg/m³ - Temperature measurement range: 0 - 50 °C - Humidity measurement range: 20% - 90% relative humidity - Battery: 1200 mAh lithium - ion battery - Standby time: about 240 - 360 minutes - Charging time: about 4 hours - Service life: about 2 hours - USB interface: Type - C interface - Input voltage: 5V/1A - Working environment: 5 - 40 °C, humidity less than 90% relative humidity - Colors: black, orange - Material: plastic G. Package contents: - 1 air quality detector - 1 USB charging cable - 1 English instruction manual Only the above package contents are included, and no other products are included. H. Note: Light and different displays may cause slight differences between the color of the item in the picture and the actual product. The allowable measurement error is ±1 - 3 cm.