A key piece of second world war history is set for auction later in the month.
One of a small number of surviving Nazi enigma machines comes to Christie's with a £30,000 to £50,000 estimate on September 29.
The encoding machines, which the Germans thought to be indecipherable, were used by the Nazis to send messages during the second world war.
"It is rare for one to come up for sale," Christie's James Hyslop told US news channel CNN.
"Many are believed to have been produced but it's not a particularly high survival."
Hyslop added that the price for historically significant scientific pieces has not been hit by the global financial crisis, suggesting that we could be in for an impressive showing.
The Germans bought the machines from the Dutch in 1929.
Following preliminary work by Polish experts, it took a crack team of British code breakers housed at Bletchley Park, Buckinghamshire to unravel the messages produced by the machines, which could scramble codes into millions of different combinations.
The team, codenamed Ultra, has often been praised with shortening the war by two years through obtaining knowledge of German movements ahead of time.
Ultra was deciphering around 6,000 messages a day at the peak of its operations.
"It was thanks to Ultra that we won the war," Winston Churchill told George VI following the Allied victory.
We will bring you news of the sale later in the month.