High sensitivity microphone：Equipped with a high-sensitivity microphone in the low frequency range as standard. It is effective for long spans of large belts Wide measurement frequency area：The 3-step range switching allows measurement of a wide frequency range from 10 to 5000Hz.IMPROVED frequency ranges: LOW (10-50 Hz), STANDARD (10-1000 Hz), HIGH (900-5000 Hz) Equipped with auto trigger function：Once you press the "MEASURE" button, it is equipped with an auto trigger function that allows you to take continuous measurements just by flipping the belt. Automatic background noise cancellation:From the time you turn on the power until you press the “MEASURE”button, the surrounding noise environment is periodically measured and the microphone sensitivity is automatically adjusted. Pressing the “MEASURE” button fixes the microphone sensitivity. Auto power off function:The auto power off function automatically turns off the power approximately 5 minutes after the last measurement, preventing wasted battery power due to forgetting to turn off the power.