The easiest way to aim a telescope. The view seen through the window of the Telrad is continuous with the sky around it, not magnified or upside down. Three rings are lighted and appear to lie among the stars. The small ring outlines the Moon-sized area seen in the telescope. The large outer ring outlines the area seen in a standard Finderscope. To point your telescope, just look through the Telrad and move the telescope until the rings are centered on the object. The Telrad is 8 inches long. Weighs 11 ounces and mounts on any telescope without drilling any holes. It unlocks from its base for separate storage. Requires 2 AA batteries (not included).