AmScope LED-144B-ZK Black 144 PCS Adjustable LED Ring Light for Stereo Microscope & Camera, with Power Adapter 144-LED ring light providing shadow free illumination Compact design with built-in dimmer Mounting size: up to 2.48" (63mm) in diameter The ring light has 2-3/8" (60mm) inside and 3-5/8" (92mm) outside diameters 110V to 240V wide band power supplies