The OMI cryptograph was a rotor cipher machine produced and sold by Italian

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 firm Ottico Meccanica Italiana

Ottico Meccanica Italiana

Ottica Meccanica Italiana was an Italian company producing photogrammetric instruments. It was founded in Rome in 1926 by Umberto Nistri . From 1962 on, Raffaello Nistri , son of Umberto, was president of the company. Since the 1980s the company has been part of a part of Agusta. The air...

 (OMI) in Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

.

The machine had seven rotors, including a reflecting rotor. The rotors stepped regularly. Each rotor could be assembled from two sections with different wiring: one section consisted a "frame" containing ratchet notches, as well as some wiring, while the other section consisted of a "slug" with a separate wiring. The slug section fitted into the frame section, and different slugs and frames could be interchanged with each other. As a consequence, there were a large number of permutations for the rotor selection.

The machine was offered for sale during the 1960shttp://www.quadibloc.com/crypto/ro020404.htm.