A rare U.S. stamp, which originally cost 24 cents, has been sold for £184,000 ($260,000) at a British auction on Wednesday.

Warwick and Warwick auctioneers had estimated that the 1918 “Inverted Jenny” would fetch £150,000 when it went under the hammer. But the stamp, with a picture of an aircraft mistakenly printed upside down, sold for £34,000 more than expected.

“This is the first time for 50 years that this stamp has been sold outside the USA,” auction valuer Richard Beale told the Telegraph.

“There were only 100 of these stamps printed, and of those, the whereabouts of only 50 are known,” he added.

The stamp shows a Curtiss JN-4 – known as a Jenny – used for training pilots during World War I.

[Image via Telegraph]