... 4)LCD display both CO2 level and temperature Digital CO2 Monitor and Controller 1, Feature:1) ... operation)CO2 measuring range02,000ppm (default)020,000ppm, programmable selection050,000ppmtCO2 setting & Display resolution1ppmTemperature measuring/ setting range050 ... resolution10BitRelay outputOne or two dry contact outputs with programmable selection to control CO2, temperature, humidityRated switching ...