2777556

Information

• Patent Grant
• 2777556

• References
• Source

• Patent Number

  2,777,556

• Date Filed

  Not available

• Date Issued

  Tuesday, January 15, 1957
  68 years ago

• CPC

  • G09C1/12 - comprising contact-bearing permutation discs

• US Classifications

  • 380 - Cryptography