This Right-Angle Viewing Attachment can be attached to the finder of Nikon SLR cameras. With this attachment, the viewfinder image is viewed at right angles (via the built-in roof prism) to the camera's optical axis - a feature that is very convenient when shooting from low (or high) viewpoints, or when normal finder viewing is proving difficult, as can be the case in close-up work or photomicrography. It allows for setting the reproduction ratio to either 1:1 or 1:2.