Czechoslovakian 50/50 DOPLATIT Postage Due Error

Czechoslovakia · 1927 · 50/50 Heller (Postage Due)

The 50/50 DOPLATIT stamp is a rare Czechoslovakian postage due error from 1927. It resulted from a sheet of 50h 'Chainbreaker' stamps being mistakenly overprinted '50/50' for postage due purposes. This error was used by the post office before discovery, making mint copies unknown and used specimens highly sought after.

This stamp represents a significant philatelic error from the early years of the First Czechoslovak Republic, highlighting a rare instance of a misissued postage due stamp entering circulation and becoming a legendary rarity.