Postage Due Stamp, 50h on 5h Green

Czechoslovakia · 1927 · 50h on 5h

This postage due stamp features a green numeral '5' within an ornate design, originally valued at 5 haléřů. It was later overprinted in black with '50' and a horizontal bar, surcharging it to a new value of 50 haléřů. The overprint is a key feature, creating a significant and rare variety.

Issued in 1927, this surcharge was created to meet changing postal rate requirements in the First Czechoslovak Republic. The inverted overprint is a famous printing error, making it one of the most sought-after and valuable stamps in Czechoslovakian philately.