This is a 48-LED bright white ring light kit with adapter for stereo microscopes. The kit includes a LED light ring, a 110-230V power adapter and a ring mounting adapter. The inner diameter of the light ring is 2-3/8" (60mm). The mounting thread of the ring adapter is 1-7/8" (48mm in diameter). The LED ring light provides cool, even, intense and focused shadow-free illumination. It is an ideal durable cool light source for microscopes. It is brand new in original box. Its retail value is above $380. Features & Specifications: 48-LED Bright White Illumination Cool, Even, Intense and Focused Shadow-Free Lighting 60 mm Inside Diameter Fitting 35-59mm Mount Rings Coming with an 1-7/8" (48mm in diameter) Mounting Adapter More Than 100,000 Hours of Life Optimum Light Range: 2-3/8" to 5-1/2" (60 to 140mm). Power Input: 110-230V, 50-60HZ, Auto-Switching. Great for Most Stereo Microscopes