The design of its successor had begun by February 1937. In June 1938, Typex Mark II was demonstrated to the cipher-machine committee, who approved an order of 350 machines. The Mark II model was bulky, incorporating two printers: one for plaintext and one for ciphertext. As a result, it was significantly larger than the Enigma, weighing around , and measuring × × . After trials, the machine was adopted by the RAF, Army and other government departments. During World War II, a large number of Typex machines were manufactured by the tabulating machine manufacturer Powers-Samas.