Phase II PHT-981 Support Stand for Shore D Durometer can perform two different methods of calculating thickness measurement by utilizing the characteristics of botheddy current and magnetic induction. Testing performance is both non-destructive and extremely accurate. You can easily detect the thickness of non-magnetic coating on a magnetic substrate (ferrous) or an insulating coating on a non-magnetic conductive substrate (non-ferrous) utilizing either an integrated probe or our version that comes with an external probe.The PTG-3725 utilizes two external probes for ferrous and non-ferous substrates. Comes with 2 substrate samples(steel,aluminum), 4 calibrated thickness samples, carry case, batteries and operation manual. It can be used in many areas of industry including automotive paint measurement, manufacturing, general engineering, commercial inspection, etc.