The thermostat hood or thermostat cut out is used in microwaves. This safety device switches the microwave off if it begins to overheat. It closes with heat to run the vent fan and ensure the temperature is at a safer level. If your thermostat hood is broken or damaged, it can affect the safety of the microwave. In this case you may need to replace this part to solve any problems and prevent future damage. The measurements for this part are: 0.8 inches in length, 0.6 in width, 1.2 inches in height, and weighs 0.05 pounds. Remember to unplug your appliance from the power source before beginning this installation. Refer to the manual provided by the manufacturer for further installation instructions.