No original packaging, no instructions

PRECISE PARTICLE MONITOR: This home air quality tester uses a pre-calibrated, precise, professional particle sensor to accurately detect particulate matter and PM 2.5, which pose a huge threat to human health.

4 IN 1 MULTIFUNCTIONAL METERS: A small device with big functions, it can also be used to detect formaldehyde and TVOC to tell you how clean or polluted the air in your room is and help you understand when to take action to protect your health.

10 YEARS OF PM2.5 SENSOR RESEARCH AND DEVELOPMENT: Using Temtop's industrial-grade PM2.5 laser sensor and the British Dart formaldehyde sensor. Professional, high-tech components ensure the highest precision and professionalism in detection.

Easy to use: One button controls power on/off, interface switching, and the auto loop function. Three color LEDs indicate air quality from healthy to unhealthy. HCHO sensor calibration is also available.

WHY TEMTOP: We have partnered with other professional sensor suppliers worldwide, such as Senseair/Sensirion/Renesas, and have been selected and recognized by several public organizations, including UChicago and Washington gov.