These are military issued IR US flags worn for Friend or Foe identification. The flag is made of material that reflects when viewed under IR light.
US Flag IR Patch
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Why the American Flag Is Reversed on Military Uniforms
Infrared Reflective American Flag Patch Reverse
IR.Tools Garrison Infrared IR Forward American US Flag Patch - 3x5
Brazilian Army Issue PVC Flag Patch-BRAZFP
Cheap LIBERWOOD Welsh Flag Embroidered Military Shoulder Applique Wales Multicam IR Reflective Hook Loop Patch Tactical Badge Emblem
Genuine Reflective (mil-spec) USA Flag patch. White light reflective, non-fabric Glo-Tape patches with Velcro® hook backing attaches to Velcro® on
Full Color (white light reflective) US Flag uniform Patch USA Military (choose size) — Empire Tactical USA
My Base Guide - Why Is the Flag Backwards on Military Uniforms?
Usa Flag Patch Badge Embroid, Usa Flag Iron Patch
USAMM - Full Color Infrared U.S. Flag Patch - Forward
Authentic US MILITARY- IR -INFRARED REFLECTIVE- Forward-BLACK- US FLAG VEL PATCH