2345636

Information

• Patent Grant
• 2345636

• References
• Source

• Patent Number

  2,345,636

• Date Filed

  Not available

• Date Issued

  Tuesday, April 4, 1944
  80 years ago

• CPC

  • E21F1/04 - Air ducts

• US Classifications

  • 138 - Pipes and tubular conduits
  • 454 - Ventilation