Digital decibelmeter Habotest HT622B USB A/CHabotest HT622B Volume Level Meter The HT622B volume level meter features high sensitivity and will work well in many applications. The color LCD display will provide you with the most important information, and the additional wind shield ensures accurate measurement regardless of the conditions. The device offers several modes of operation, and thanks to the possibility of connecting it to a computer via USB, you will gain convenient access to data.