The DeFelsko 200D1-G Positector 200 D1 Standard Ultrasonic Coating Thickness Gages for Non-metal Substrates, 2 - 300 mils is DeFelsko PosiTector 200D1-G non-destructively measures a wide variety of applications using proven ultrasound technology. The DeFelsko 200D1-G Positector 200 D1 Standard Ultrasonic Coating Thickness Gages for Non-metal Substrates, 2 - 300 mils is PosiTector 200D1-G measures thick, soft coatings like polyurea, asphaltic neoprene, very thick polymers.