NOYAFA Portable Formaldehyde Detector Indoor Air Quality Monitor HCHO and TVOC Monitor with Audible Alarm LED Indicator for Home HVAC System

Features:
Using advanced chip to accurately detect and monitor the concentration of formaldehyde(HCHO) and total volatile organic compound(TVOC).
Immediately send out audible and visual alarm if the concentration of HCHO and TVOC exceed the normal level.
Super easy to operate, long press the button to power on, wait for a 180s countdown, and it will automatically monitor the HCHO and TVOC contents.
Easy to read, 3-color LED indicator shows you the level of TVOC - bad, normal, good.
Precision air quality monitor features rounded shape, glossy surface, compact and lightweight, easy to carry around.
Note:
*Batteries not included.
*Under normal battery level, the unit will enter standby mode after 30 minutes if there is no operation taken.
*Under low battery level, the unit will enter standby mode after 5 minutes if there is no operation taken.