http://yghap.com/air-quality-monitor/Air-Quality-Detector-7.html

With the continuous development of industrialization, the air quality of our lives is getting worse. This forces us to pay close attention to changes in air quality. In view of this demand, our company has introduced a new pm2.5 air quality detector to help us monitor air quality changes more convenient.Different from the large sizes of previous air quality detectors, our new detector is designed as small stone, which is very easy to carry. YGHA10 pm2.5 air quality detector uses Led digital display with 180 degree angle, the pm2.5 digits occupy most area of the screen so you can see it clearly in a far distance. Built-in lithium battery let you measure PM2.5 value at anytime and anywhere. After charging full, it could be used for 5 hours. This air quality detector working environment is -9~50 degree, and the  humidity range is 20%~90%RH, so you can use it at ease. This pm2.5 air quality detector measure the pm2.5 in the air by laser scattering, there is a built-in sensor in it. And the pm2.5 measuring range is 0~999ug cubic meter. When the value display on the screen is below 50, it shows the air quality is good. 51~100 shows the quality is moderate. Under these two conditions, the value display in green. But if the value is in 101~150, it shows the air quality is unhealthy for sensitive groups. When the value is in 151~200, it shows the air quality is unhealthy for all groups. In 201~300, it shows the air quality is very unhealthy. When the value is above 300, it shows the air quality is hazardous, we have to do something to improve the air quality at that time. While the value is above 100, the value will display in red and flashing. And the measure resolution is 10ug per cubic meter.

If the place you lived in is in poor quality, don’t hesitate and buy it quickly.