This is a 56-LED ring light with built-in intensity control and mounting size up to 2-3/8 (60mm) in diameter. The ring light has 2-3/8 (60mm) inside and 4 (100mm) outside diameters. It works with power supplies from 110V to 240V. It comes with a 1-7/8 (48mm in diameter) ring adapter. With variable intensity control it provides cool even intense and focused shadow-free illumination. It is an ideal durable cool light source for microscopes. This kit comes with one year warranty against manufacturing defects. Features & Specifications: 56 bright white LED bulbs Built-in intensity control 100 000 hours of life Intense and focused shadow-free illumination Variable intensity control Mounting size: up to 2-3/8 (60mm) in diameter Inside diameter of the ring light: 2-3/8 (60mm) Outside diameter of the ring light: 4 (100mm) Power input: 110-240V 50-60HZ auto switching Packing List: One 56-LED Ring Light One Power Adapter One 48mm Ring Adapter