Magnetic thickness gauges are instruments used to measure the thickness of non-magnetic coatings on magnetic substrates, such as steel or iron. They work by utilizing the principles of magnetism, where the gauge measures the strength of the magnetic field to determine how thick the coating is. This is essential in industries like automotive and construction to ensure quality control and compliance with safety standards. These gauges are typically portable and easy to use, making them suitable for both field and laboratory applications. They can provide quick and accurate readings, helping professionals assess the condition of coated surfaces without damaging them. This efficiency is crucial for maintenance and inspection tasks.