The adapter has the 0.3x reducing relay lens built into the removable top section that also includes the C-mount male threads. The adapter is designed for video cameras with a 1 inch sensor or a 2/3 inch sensor, depending on which photo eyepiece is installed in the trinocular head of the BH-2 compund microscope. Either the NFK 2.5x photo eyepiece or the NFK 1.67x photo eyepiece can be used. The 2.5x is commonly available and has the advantage that it is also usable for adapters that attach a DSLR to the microscope. More information about how to use this adapter and C-mount lenscan be found on Alan Wood's excellent website: see attaching aC-Mount video camera to an Olympus BH-2 microscope.This item is in the category "Business & Industrial\Healthcare, Lab & Dental\Medical/Lab Equipment Attachments & Accessories\Microscope Parts & Accessories\Microscope Camera & Lens Adapters".7107" and is located in this country: US. This item can be shipped to United States.