A coating thickness gauge provides quality control for many products and materials, such as steel and iron. Cars, ships, planes, industrial components and even mobile phones, as well as hundreds of other articles are all coated, generally using high-tech processes. On the one hand, such products require effective protection (e.g. against corrosion), with the aid of coating thickness measurement, to lengthen service life; on the other, they need to look good. Both aspects are equally important for customers, because both a product’s design and service life are vital factors in purchase decisions.