5M means Machinery, Manpower, Material, Measurement, and Method in Military
Similar to 5M
12 WVI - Twelvth West Virginia Infantry Regiment121ARW - 121st Air Refueling Wing
129 RQW - 129th Rescue Wing
12N - Horizontal Construction Engineer
13 SCVI - 13th South Carolina Volunteer Infantry Regiment
13AD - 13th Airborne Division
13B - Military Occupational Specialty code for Cannon Artilleryman
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