Instead of spending hundreds to thousands of dollars on an ultrasonic paint thickness gauge, we can instead use an affordable magnetic/Eddy-current gauge as long as we have an understanding what the typical layers on a modern day car are, what the thickness of these layers are. By knowing the typical thickness of each layer that encompasses a “paint job”, we can have a general idea of how much clear coat we have before we wear down to the paint, primer, or even substrate.