The instrument is to measure ! (Quality factor) of an inductor. which is necessary to know when designing coils or transformer, measuring frequency is 1 KHZ or 10 KHZ. Measuring range is 0.1 to 100. Moving coil meter is used as indicator. Workable 220 V 50Hz. Balancing dial is directly calibrated in terms of Dimension : 14"x9"x5½"