The MMX-6 Through Paint Ultrasonic Wall Thickness Gauge, Complete Kit is used to measure wall thickness and the extent of corrosion of all metals, ceramics, glass and most rigid plastics - from only one side!The MMX-6 can be used in a Single Thickness Reading mode or in a Scan mode , where the probe is dragged over a large measuring area. The minimum thickness reading recorded during the "scan" will be displayed. The MMX-6 probe is waterproof and can be submerged in water. The gauge is impact-resistant and environmentally sealed to provide trouble-free operation under the toughest field conditions. The MMX-6 is supplied as a complete kit with the gauge, probe, 4 oz. bottle of coupling fluid, 2 AA batteries, NIST-Traceable Calibration Certificate, and Operating Instruction Manual - all in a foam-fitted carrying case.