This is a US Army Rucksack.  Comes from the home of a 1980's Special forces soldier.  The Lightweight Rucksack Nylon pack with removable external Lightweight aluminum frame was developed as part of the US Army's efforts to develop suitable equipment for use by Special Forces, LRRP,and mountain and artic forces.  Is in good overall condition, was used in South America so expect some signs of usage.  Again look at pictures closely.   Feel free to make offer.