Unused in mint condition in the original military packaging. Complete prism cluster (right side) for your M16/17 7x50 binoculars and fits many others! Well made mounted two prism erecting assembly is what you need for building a spotting scope or monocular. Two mounted porro prisms, 2 inches long by 1 inch high. Assembly is 2-1/2 inches thick by 2-1/2 inches diameter and the view openings are 1 inch diameter. Coated optics, unused!