Since means a lot to one, the 5-in-1 air quality monitor will be your best . It can accurately monitor CO2, TVOC, HCHO, humidity& temperature. You can monitor the environment at any time. Equipped with a fast-responding and sensitive high-performance chip, the air quality monitor can precisely capture the weak currents generated during electrochemical reactions. Dual color & voice alerts keep you informed of the current air quality conveniently. Built with 1200mAh rechargeable battery and packaged with one 5V USB cable, the standby time can last for 10 hours. Never be anxious about low power. The mesh design allows for better heat dissipation during operation, preventing the device from hot, and more accurate measurement data. Color: white Material: ABS Package Contents: 1X Air Quality Monitor Tester 1X USB charging cable 1X English Manual 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.