Mepro Mx3 Magnifier Meprolight.
Manufactured to the highest military standards to assure years of reliable operation under all field conditions, the MEPRO MX3 extends shooting ranges with no need to re-zero the sights. Any soldier can use it easily and benefit from its advantages. The MEPRO MX3 magnifying scope attaches to any standard MIL-STD-1913 Picatinny Rail behind a reflex sight, by means of a quick release adapter.
Big Book Catalog, Issue:71, Page:279