Product feature: A 54 or 56 bright white LED bulb ring light kit for microscopes. The kit includes a 54/56-leds ring light with 2-3/8" (60mm) inner diameter, a 110-240v power 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. Its retail cost is above $300 in us and around $200 in China. Product specifications 1,54/56 bright white LED bulbs. 2,20,000 hours of life. 3, cool, even, intense and focused shadow-free illumination. 4, variable intensity control. 5, optimum light range:2-3/8" - 5-1/2" (60 to 140mm). 6, power input:110-240v,50-60hz, auto switching. 7, fits 35-59mm mount rings.