A pocket sized set of 3 UTM corner rulers or "roamers" for 1:24,000, 1:25,000, and 1:50,000 scale maps. The 1:24k and 1:25k corners allow you to divide a 1km map grid to a 10m precision. The 1:50k corner allows you to divide a 1km map grid to a 20m precision. The tool has a hole at the corner of each scale to allow for placing a mark on the map. There is also a hole in the center that allows a string to extend the compass rose. There is a lanyard hole in the upper left corner. Approximate size is 2.75 x 2.75 in (7cm X 7cm).