AmScope LED-60-YA 60 LED Microscope Ring Light with Mounting Adapter Ring light with 60-LED bulbs provides strong shadow free illumination Comes with a control box for light intensity adjustment 1.77" (45mm) inside diameter and 3.35" (85mm) outside diameter Mounting size: up to 2.4" (61mm) in diameter Power supplies: wide band voltage from 100V to 240V