Digital Ultrasonic Thickness Gauge Meter Tester 1-300mm Tool for Metal Cast Iron

（Does not work with cast iron）. Note: The coupling gel is Not included. WT130A Features:(WT130A Work With cast iron, WT100A NOT fit). Adjustable Sound Velocity: You can be easily changed sound velocity from 1000 to 9999m/s to get the most accurate results.

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