High quality and precise Aiming Circles have general specification as topography instruments. They are used for precise measurement of Azimuth / Elevation angles of aerial or ground targets with respect to a preselected baseline as required for the orientation of artillery weapons. Using the magnetic system of the instrument, you can define the magnetic poles of the Earth precisely and then the target can be identified. They were equipped with illuminating reticule system with controllable light and sun filter. They were protected against water, dust, rusts