Hygrometers; Thermo-hygrometers; Air analysis apparatus; Electric sensors; Electronic-based instruments for measuring environmental parameters including humidity, mold, bacteria, air quality and water quality; Fire and smoke detectors; Gas detectors for detecting the presence of gas; Gas meters; Gas sensors for measuring gas concentration; Safety sensors, namely, carbon monoxide detectors, smoke detectors, and combination carbon monoxide and smoke detectors; Scientific instrumentation for mea...