NSA National Security AgencyConfederate Cipher Wheel (disc) The principal encipher/decipherment system used by the Confederate government and military was based on a centuries old system known as the "Vignere system", called the "Vicksburg system" by the Confederate States of America. The pocket-sized cipher disc was developed for the use of signallers. This cipher disc is a faithful replica of the original. (At most five are known to exist.) One of these original cipher discs was given to the Museum of the Confederacy in Richmond, Virginia, by Major Graham Davis who, as Assistant Adjutant to General S. G. French, used it to encipher and decipher messages for his commander. Cipher discs were probably made at the request of E. P. Alexander who, in 1861, was ordered to establish a Confederate Signal Corps. This authentic, metal cipher disc really works! Comes in its own protective velvet pouch and a plastic case for added protection. Please email with any questions.