Coating Thickness Gauge is capable to measure thickness of non-magnetic coating layers covered on magnetic substrate. Such as: non-magnetic (aluminum, chrome, copper, enamel, paint) covered on magnetic substrate (steel, alloy and magnetic stainless steel), also can measure thickness of non-conductive coatings layers covered on conductive substrate. Such as: (enamel, rubber, paint, plastic) covered on conductive substrate (aluminum, brass, zinc and nonmagnetic stainless steel);