USNG is standard that established a nationally consistent grid reference system. It provides a seamless plane coordinate system across jurisdictional boundaries and map scales; it enables precise position referencing with GPS, web map portals, and hardcopy maps. USNG enables a practical system of geoaddresses and a universal map index. This data resides in the GCS 1983 coordinate system and is most suitable for viewing over North America.
For more information please visit http://www.fgdc.gov/usng
