A rare 1944 M4 4-rotor Enigma machine will auction at Bonhams London on May 18.
The lot is one of around 120 surviving Naval M4 machines - employed by the Germans for sending encrypted messages during the second world war. This example was captured from a U-boat.
The 4-rotor M4 Enigma machines were mainly used by the German navy
These are particularly rare, as the majority were destroyed before the vessels could be boarded.
It's valued at around £100,000-150,000 ($145,605-218,408).
A new record for an Enigma machine was set at Bonhams last year for another 4-rotor specimen captured from a U-boat. It achieved $365,000.
The Enigma code was originally cracked by a team of Polish mathematicians in 1939. Alan Turing famously advanced the techniques, allowing the British to translate messages.
The breakthrough was only revealed in the 1970s.
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