MIL-DTL-48554 Telescope, Panoramic - M137A2, M137A3, And M137A4This specification covers Telescope, Panoramic ?√ M137A2, M137A3, and M137A4 which are types of panoramic telescopes which provide four-power magnification and a ten-degree field of view. They are equipped with numerical counters which indicate azimuth settings and corrections.