The Fialka is an electromechanical, wheel-based decoding and code-generating machine that was developed after WWII by the Soviets. The codename Fialka, which is actually the name given to the cipher procedure rather than the machine itself, means ‘violet’ in Russian. These machines worked by scrambling the letters and numbers typed on the keyboard, creating an encryption.
The device was first introduced in 1956 with the M-125 model, which was produced in the Soviet Union. The majority of these models could only encrypt and decode messages in Cyrillic. An improved version, the M-125-3M, was used from 1965 onwards and these are the two basic versions that are known to have been used during the Cold War.