Autopilot Digital CO2 Controller with Integrated SensorThe new Autopilot CO2 Monitor & Controller with Integrated Sensor offers a simple and affordable way to control, monitor, and record CO2 levels. Operation modes are CO2 enrichment or CO2 exhaust. The new CO2 Exhaust mode will trigger an exhaust fan to reduce CO2 levels. This is an ideal safety function for humans working in confined spaces. Trace your room's CO2 levels over minutes, hours, or up to 7 days with this easy to use controller. The APC8400