One of the more useful items carried by Indiana Jones was his satchel/shoulder bag. A "found" item, the bag is a heavy canvas World War II-era “MkVII” (Mark Seven) British gas mask bag with the original cotton web strap replaced by a leather strap with a metal adjustment buckle.
The MkVII British Gas Mask Bag was issued to British troops and police forces during WWII as a precaution against a German gas attack. Interestingly enough, this bag actually did not exist at the time the first three Indiana Jones movies were supposed to have taken place, given that manufacturing of the MkVII did not start until 1941. However, the bag did exist by 1957, the setting of the fourth movie.
