Adjustable 60-LED Ring Light Illuminator Lamp For STEREO ZOOM Microscope US plug Package Content: 1 x 60-LED Lamp Ring; 1 x Power Adapter. Best Working Distance: 50mm-150mm(2"-6"). Number of LED: 60. Brightness of each LED:?MAX 3500 mcd. Power input: 100-240V, 50-60HZ.