Adopts digital temperature and humidity sensor, high accuracy, stable performance, antijamming ability, low consumption and can provides long service time. Lar LCD display, you can see the electricity quantity, CO2 value, TVOC value, HCHO value, temperature, and humidity clearly. and switchable, and the alarm sound can be on or off according to your demands. Equipped with environmental judgment function, it will display appropriate level according to measuring value. Built-in 1800mAh capacity lithium battery, easy to char it with USB cable., Manufacturer: SLZJWLPPA