Typex

For the correction fluid, see Tipp-Ex.

Typex was based on the commercial Enigma machine, but incorporated a number of additional features to improve the security. This model, a Typex 22, was a late variant, incorporating two plugboards.

In the history of cryptography, Typex (alternatively, Type X or TypeX) machines were British cipher machines used from 1937. It was an adaptation of the commercial German Enigma with a number of enhancements that greatly increased its security. The cipher machine (and its many revisions) was used until the mid-1950s when other more modern military encryption systems came into use.