The Vevor portable carbon dioxide monitor provides real-time CO2, temperature, and humidity readings for indoor and outdoor environments. It uses dual infrared NDIR sensing to measure CO2 levels from 400 to 5000 ppm with stable, precise detection. Its compact lightweight design and 2000mAh battery make it easy to carry and suitable for long monitoring sessions. The large display and three-color air quality indication help users quickly understand changing conditions in homes, offices, classrooms, cars, and greenhouses.