It is Woodland Camo pattern. If you do an internet search with the words
Fieldpack large, with internal frame . You will see images of the backpack. It also has the the attached small field pack that is part of the entire backpack system.
I don't know alot about packs but at a recent gunshow I spoke with a guy who sells Military surplus equipment. He told me that the backpack was worth 350-400 new. This is a new backpack, if your intterested I can text some photos to you.