An air-coil or bimetal sensor detects and modulates the ambient air temperature in these temperature controls. The sensor for controls with a bimetal sensor is located inside the thermostat's casing. The sensor for air-coil controls is located outside the thermostat's housing. Because the sensor is in the airstream, it provides a more precise reading than bimetal sensors. These temperature controls are appropriate for commercial and industrial HVAC applications requiring temperature monitoring at the thermostat position, such as commercial refrigeration, agricultural, and heating and cooling systems.