TM-8812 Measuring range (metric/imperial): 1.2-225mm,0.05-9inch Operating principle: ULTROSONIC Materials measured: any hard materials, including steel, cast iron, aluminum, red copper, brass, zinc, quartz glass, polyethylene, PVC, gray cast iron, nodular cast iron and other materials Sound velocity: 500-9000m/s Lower limit steel pipes: ф15x2.0mm, ф20x3.0mm determined by the transducer Calibration ...