Bletchley Park (10) Enigma
The explanatory label on the right states:
German 1842+
Enigma M4, #M18316
Knegsmarine (Naval) M4 models entered use on 1st February 1942. A 'thin' reflector made space for a 4th rotor. From its introduction, this model proved far harder to 'break' and seriously reduced available intelligence re U-boat activity in the Atlantic. The M4 had to be mastered by BP or the UK risked losing the war - simply due to our convoys' losses. This particular example was made in 1944.
Bletchley Park (10) Enigma
The explanatory label on the right states:
German 1842+
Enigma M4, #M18316
Knegsmarine (Naval) M4 models entered use on 1st February 1942. A 'thin' reflector made space for a 4th rotor. From its introduction, this model proved far harder to 'break' and seriously reduced available intelligence re U-boat activity in the Atlantic. The M4 had to be mastered by BP or the UK risked losing the war - simply due to our convoys' losses. This particular example was made in 1944.