This is a 64-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. It is brand new in original box. Features & Specifications: 64 bright white LED bulbs Built-in intensity control 100,000 hour lifetime 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 64-LED Ring Light One Power Adapter One 48mm Ring Adapter