The Beyer pocket cryptologic device from the 1930s resembles the size and appearance a pocket watch of the era. Only about a half-dozen examples of the Beyer device are known to exist. The Beyer device consists of two disks, or rings carrying two dials divided into 26 or 30 slots in which the alphabet is written — alphabetically or other. The possibility of decoding messages encrypted on the Krypto device is extremely small since there are 7034 × 1061 combinations.