Calibration block PCE-USC-V2 for PCE-USC 20, PCE-USC 30, and PCE-FD 20. Distance, beam index, refracted angle, and sensitivity calibration. Contains a 1.0" radius opposite a 2.0" radius, a 5/64" diameter x 0.750" deep flat-bottom hole. In accordance with ASTM E164 specifications. Dimensions are 1" thickness.