Plastimo IRIS 50 MILS Widely considered as the ULTIMATE Military Compass. Used by different forces around the world the IRIS 50 doesnt require ICE checking (individual compass error) The viewfinder is clear and accurate for both day and night use, although we would suggest you seriously consider purchasing the Photoluminescent Back Plate, which makes reading instant, even when you have just imerged from a white light source into the dark. Features: •The internal workings are interchangable. •Doesn't need ICE checking. •Back plate is interchangable. •Easy to hold with gloves •Rugged and tough