The SU-330C long probe manual ultrasonic hardness tester is also known as ultrasonic gear hardness tester and deep hole hardness tester due to its small ultrasonic probe, which can non destructively measure workpieces such as gears and deep holes that cannot be directly measured by ordinary hardness testers. The SU-340T short probe manual ultrasonic hardness tester is also known as an ultrasonic pipeline hardness tester or inner wall hardness tester due to its very short ultrasonic probe configuration, which can directly measure the hardness of the inner wall of the pipeline without damage.