Encountering this series of “Tulip” stamps, I assumed because of the subject, the clean contemporary design, and the PTT POST imprint, that these were from the Netherlands. There was, however, no monetary value on the stamps.
The other bit of information on the stamps was PORT BETAALD (“POST PAID” in Dutch). Further investigation led to the fact that these were used for Bulk Mailing.
I was drawn to these stamps for their beauty—a refreshing approach to bulk mail stamps, which in the U.S. are generally quite bland in design. Perhaps even junk mail can bring a smile to your face, provided the stamp is appealing.