Yes, that's probably it. For clarity, I've attached another photo.
In terms of comfort, without a hip belt, it's only designed for light loads. But it only has a capacity of 35 liters, which is very small for military use. For me, however, 35-40 liters is often enough.
I bought it at a flea market a few years ago. Since I enjoy tinkering and sewing, I will continue to use the frame and give it a new bag. In the process, it will also get new straps and a hip belt. With that, it will probably weigh almost as much as my normal base weight ;-)