1.Sharp stereo erect image over a wide field of view 2.The left ocular-tube with diopter adjustment ±5dp.The interpupillary distance is between 55－75mm. 3.V-shape inserted style objective with locked-in device ensures easy replacement. 4.Power supply 110V/60Hz or 220V/50Hz. 5.Optional accessories:Eyepiece WF5×,WF10×,WF15×,WF20× Objective: 0.5X, 1X or 2X 6.Illumination: Incandescent lamp 12V10W/6V/6W and High brightness LED lamp for selection.