These machines were probably build for the Japanese Navy and were sitting in a warehouse in France when they were captured by the Allied forces. Apparently the machines were never used in an operational context.

The Enigma 'K' is a three-wheel machine with a settable UKW. It has no Steckerbrett and is based on the commercial Enigma. The machine is special as the ETW does not have the usual ABCDEF... or QWERTZU... diagonal, but a random permutation instead.

The wiring of wheel IV was obtained from NARA records by Philip Marks.