This is an intensity-adjustable 80-LED ring light with mounting size up to 2-1/2 (65mm) in diameter. The ring light has 2 (51mm) inside and 4 (100mm) outside diameters. It works with power supplies from 90V to 265V. It comes with a 1-7/8 (48mm in diameter) ring adapter. This light it provides cool even intense and focused shadow-free illumination. It is an ideal durable cool light source for microscopes with one year warranty against manufacturing defects. Features & Specifications: 80 bright white LED bulbs 100 000 hours of life Intense and focused shadow-free illumination Variable intensity control Power input: 90-265V 50-60HZ auto switching Fits up to 2-1/2 (64mm) mount rings Inside diameter of the ring light: 2 (51mm) Outside diameter of the ring light: 4 (100mm) Packing List: One 80-LED Ring Light One 48mm Ring Adapter