2808452

Information

• Patent Grant
• 2808452

• References
• Source

• Patent Number

  2,808,452

• Date Filed

  Not available

• Date Issued

  Tuesday, October 1, 1957
  67 years ago

• CPC

  • H04L12/04 - Switchboards

• US Classifications

  • 178 - Telegraphy
  • 455 - Telecommunications