Magnetic Thickness Gauges are instruments used to measure the thickness of non-magnetic coatings on magnetic substrates, such as metal. They work by utilizing the principles of magnetism, where the gauge detects the strength of the magnetic field to determine the distance between the surface and the substrate. These gauges are commonly used in industries like automotive, aerospace, and manufacturing to ensure quality control and compliance with safety standards. They provide quick and accurate measurements, making them essential tools for assessing the integrity of coatings and preventing corrosion or damage to the underlying material.