3639020

Information

• Patent Grant
• 3639020

• References
• Source

• Patent Number

  3,639,020

• Date Filed

  Not available

• Date Issued

  Tuesday, February 1, 1972
  53 years ago

• CPC

  • B42F15/0029 - suspended in the middle
  • B42F15/0023 - with single suspension means
  • B42F15/0058 - with fixed suspension means

• US Classifications

  • 229 - Envelopes, wrappers, and paperboard boxes