Originally produced for the U.S. Armed Forces.
Model 183
Contains trituim filled vials that provide a bright green flourescence allowing the compass to be read at night without an external light source.
Operating temperature: -50 to +160F
Military Lensatic Compass
Graduated Azimuth (0-360 degree) in 5 degree units, the outer portion of the dial is graduated in mils. Sturdy aluminum case with metal hinges, painted olive green. Waterproof and shockproof. Built-in magnifying lens and 1:50,000 map scale die-cast on the side. Dampened by an inner copper shell that allows for fast settling of the needle. Includes finger loop for holding compass steady, nylon lanyard and nylon carrying case with "Alice" belt clip.