3903707

Information

• Patent Grant
• 3903707

• References
• Source

• Patent Number

  3,903,707

• Date Filed

  Not available

• Date Issued

  Tuesday, September 9, 1975
  49 years ago

• CPC

  • E21D19/04 - for use in drifting galleries
  • E21D9/0692 - Cutter drive shields

• US Classifications

  • 405 - Hydraulic and earth engineering