Product Description MH-Z19C Carbon Dioxide Gas Sensor (hereinafter referred to as the sensor) is a general-purpose intelligent small sensor, the use of non-dispersive infrared (NDIR) principle of the presence of C02 in the air to detect the characteristics of very good selectivity, no gas-dependence, long life, etc.: Built-in temperature compensation; at the same time, with a serial output, analog output, PWM output, easy to use. The sensor is a high-performance sensor made by closely combining the mature infrared absorption gas detection technology with precision optical circuit design and refined circuit design