Interesting question, and debatable. Most FAK's even the one I carry is usually for small traumas and daily discomforts. In the event of a large situation such as a train wreck, building collapse, Bombings, and even motor vehicle collisions I don't think you could carry a large enough FAK, even my Trauma kits I carry on my ambulance unit may not have evrything a medically trained individual would need.
But I will list the items I find that I reach for frequently when I am called to large trauma scenes.

Gloves (multiple pairs)
Blood Stopper Bandages
4 x 4's
2" medical tape
CPR Mask(s)

Hope this helps

Ted Fisher ILLINOIS EMT I/D
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