This is a new Calectro VU Mini-Meter, in its original box with rubber mounting washer and plastic mounting nut. The panel is 1-1/4 inches square and the round threaded body will fit through a 1-1/8 inch hole, maybe 1-1/16. The scale reads from -20 dB to +3 dB. The model number is shown on the box as D1-958, and on the panel as DI-958.