This is a 144-LED intensity adjustable ring light for stereo microscopes with mounting size 2.4" (61mm) in diameter. The ring light has 2.5" (62.5mm) inside and 3.64" (92.5mm) overall outside diameters. It works with power supplies from a 100-240V and comes with a 1-7/8" (48 mm in diameter) ring adapter. With variable intensity control, i