Back in the days, business cars were called trade cards and businessman of those days would distribute to clients and potential customers just like we do now. The design on this cards is the only thing that actually changed over the year.
Even though some of these stamps are not so vintage, most of them are from the 70's with strong designs from all over the world including some amazing pieces from switzerland. It's really nice to see and compare what they were doing back them without half of the technology that we have now days. Enjoy!
These stamps were found at Adapt or Die Flickr gallery, visit them for more.