primitive old factory spools of vintage thread, heavy duty industrial sewing thread

Lot of vintage heavy duty sewing thread, supple but faded and spotted from age. These are big plastic spools, most are 6 1/2" tall, they range in size from 1 1/2" to 3" in diameter. This lot is all grubby brown colors, and would make a lovely primitive / rustic display.

We're not sure of the fiber content of all of these threads, though we'd guess most are nylon thread? It looks like thread for sewing bags or luggage, tents, or shoes. It's quite heavy thread, and very strong!