I have included a couple of feet of flat pack duct tape in all of my FAK's after a recent incident.

I had a pallet fall against my shin at my job, I had on shorts, and peel a 1"x12" strip of skin off of it.
The first aid tape that I had in the FAK lasted about 3 seconds on my sweaty skin. But the duct tape I had in my bag, stayed put for hours. Long enough for me to finish my deliveries and get back to the depot.

When I got home my wife just rolled her eyes.

Lesson learned: You can never have enough duct tape.