This is a 144-LED intensity ring light for stereo microscopes with mounting size 61mm in diameter. The ring light has 62.5mm inside and 92.5mm overall outside diameters. It works with power supplies from 100-240V. It provides a cool, even, intense and focused shadow-free illumination. It is an ideal durable cool light source for most of our stereo microscopes and fits all our SMZ series.