NSN: 6675-00-266-6880 Just like the trusty GTA 5-2-12, this improved version from RM Products will never steer you wrong. The only known back up of the GPS when it malfunctions is your ability to use a military protractor and military compass. Great skills to have! The RM Military Protractor is the only protractor with a printed formula and a diagram to align map grid north to match the compass magnetic north. Protractors without the conversion formula will provide a reading that is off the exact grid coordinate position.  1:25,000 x 1km/1:250,000 x 10km1:50,000 x 1km1:100,000 x 1kmThe scale has three die cut triangles for access to mark the map being measured. The inner protractor is marked in degrees and the outer protractor is in mils. Compass Rose in both Degrees and Mils. Measures 5" x 5" square, just like the original.