This Lecoolife air quality monitor is $32.98, down from $49.99. It’s the best price Amazon has charged for this model. It tracks eight readings, including CO2, formaldehyde, and TVOC levels, in a compact 4.8 oz. body that runs on a rechargeable battery for portable use at home, in the car, or on trips. A silent mode lets you monitor air quality without audible alerts, useful for bedrooms or overnight checks. Buy Now at Amazon