... vortex thickness measurement method, can detect the thickness of non-conductive coating (such as:rubber, paint, plastic, anodic oxide film,etc) ... use both magnetic and vortex thickness measurement methods,can detect the thickness of non-magnetic coating(such as: zinc, aluminum, ... , etc.) and the thickness of non-conductive coating(such as:rubber, paint, plastic, anodic oxide film,etc) on non-magnetic ...