This is an authentic East German RPG-7 Canvas Sling. The RPG-7 is a portable, rocket-propelled grenade launcher and this sling is adjustable and comes with sturdy, spring loaded metal quick-release clips at either end to attach to the RPG. Both clips are in working order.
The RPG-7 was first delivered to the Soviet Army in 1961 and deployed at the squad level. It replaced the RPG-2, having out-performed the intermediate RPG-4 design during testing.