Santacary Pocket HCHO Monitor Detector, Formaldehyde Oxymethylene , Temperature and Humidity Air Quality Monitor FH20, Mini AQI Datalogger Indoor Indicator Fairyland FH20 is a mini style, precise indoor air quality monitor suitable for monitoring low level concentrations of hazardous formaldehyde vapors in both ppm (parts per million) and mg/m3. Up to now, FH20 should be the smallest formaldehyde monitor in the world. It cans measure formaldehyde concentration in a range of 0-5ppm and a resolution of 0.01 ppm. With fully charged, FH20 is capable of over 14 days continuous monitoring formaldehyde concentration showing in trend curve and help people to understand the changing of Indoor Air Quality. In addition to measuring the formaldehyde concentration, the Fairyland FH20 can also measure the ambient temperature and the relative humidity. With its accurate, small size and lightweight, Fairyland FH20 can be widely used in the new office, new home, super market, gardening, furniture, wooden floor, indoor decoration, medical, food, wall papers, construction materials construction, paper manufacture, industrial safety, labor-working place, etc. for indoor formaldehyde gas detection, test and verify the efficiency of the air purifier and formaldehyde removing detersive. Electrochemical sensor for formaldehyde detection, no consumable parts. Trend display available for easy understanding about HCHO change. A mini, lightweight pocket Formaldehyde Meter/Monitor with thickness of 17mm and weight of 2.25 oz. Visible HCHO warning alarm when HCHO concentration exceeds the set limits. Low power: Provide max 14 days of continuous HCHO/Temp/RH monitoring after fully charged.