Multi-tools similar to that were sold new in the 1970's-1980's, possibly after that as well. I picked up a double-end-ball style with four different hex sizes on the sides of each ball and a smaller opening on the ends.

Neat items when you find them and worth whatever price that will keep the smile on your face. If you smile goes away then the price is too high. Some are made out of pot-metal or some cast aluminum alloy, I've seen others that appeared to be made better and were actually machined.