O7 means Officer grade: Commodore, Rear Admiral Lower Half, or Brigadier General in Military
Similar to O7
21CLW - 21st Century Land Warrior21CLWTLD - 21st Century Land Warrior Top Level Demonstration
24 MEU - 24th Marine Expeditionary Unit
24NAF - 24th Numbered Air Force
26PEMR - 26th Pennsylvania Emergency Militia Regiment
278 ACR - 278th Armored Cavalry Regiment
2AD - 2nd Armored Division
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