Military compasses run the gamut from lensatic, prismatic, sighting, and even little bits of metal that you don’t realize are a compass at all; perhaps disguised as a collar stay, or a button.

Many designs for sporting compasses derive from military needs.  Many military compasses are graduated in mils (milliradians), used primarily by the military, because it allows the user to gauge horizontal distances (1 mil is approximately equivalent to a horizontal distance 1/1000 of the range to target). Some are graduated in both mils and degrees, and some are in degrees only.