Ultrasonic Thickness Gauge TG-3250 with probe with contact diameter of 5mm single element, it can check for fake gold coins where the contact diameter for the probe shouldn’t exceed 5mm. The model of the gauge TG-3250 allows manual setting of the velocity.
TG-3250 is a high precision digital ultrasonic thickness gauge. Based on the same operating principles as SONAR it is capable of measuring the thickness of various materials with resolution as high as 0.001 millimeters, or 0.0001inches. It is adapted to measure the thickness of good conductor for ultrasonic, such as metal (steel, cast iron, aluminum, copper), plastic, ceramic, glass, glass fiber and so on.