U.S. Army M1943 Mountain Backpack - Rucksack with a metal frame. Manufactured by Avery (stamped on cover).
This was one of several designs developed by the J.Q.D. in order to provide a better pack solution for mountain troops. The standard combat rigging haversacks were unfortunately insufficient for carrying the amount of gear needed when there were no vehicles to carry supplies. As such they designed these metal frame packs to solve the issue. The metal frame itself measures about 17 1/2" wide x 21" tall x 6" deep, so once fully loaded this was a large pack.
Was my father's sking back pack for decades. He was a college skier (nordic and alpine) back east in the immediate post WWII era. Lots of good karma.
Use or display ... either way it will turn heads/get noticed