My father had a custom-fitted backpack made back around 1980, which he gave to me, and it's the best backpack I've ever used. It goes against practically everything in the book about modern backpack design. There's about zero customisability, you can adjust the length of the shoulder straps and hip strap and that's about it, but I'm a very similar build to my old man so it fits me almost perfectly. It's an external a…
Sounds very similar - it looks nothing like a modern bag, is not very adjustable, a bit heavy in comparison, super comfortable to wear and I'm pretty sure it will outlive me.