3553383

Information

• Patent Grant
• 3553383

• References
• Source

• Patent Number

  3,553,383

• Date Filed

  Not available

• Date Issued

  Tuesday, January 5, 1971
  54 years ago

• CPC

  • H04M11/027 - Annunciator systems for hospitals
  • G08B3/1008 - Personal calling arrangements or devices

• US Classifications

  • 379 - Telephonic communications