An electromechanical cipher device with a keyboard…

An electromechanical cipher device with a keyboard, a lampboard and rotating wheels, adopted by the German armed forces between the two wars. Every keypress advanced the rotors, so a letter was scrambled differently each time, and a plugboard multiplied the possible settings. Polish mathematicians led by Marian Rejewski first read it; at Bletchley Park, Alan Turing's bombe attacked the daily keys. Its wiring never let a letter stand for itself.

The answer in 13 letters