A J.M. Hays Wood Products Co. makers label, commonly found on their WW1 McClellan contract saddletrees.
This is about 1″ tall and complete is about 4″ long. This was applied on the paint applied to the tree, before the rawhide cover was sewn on. As you can see with this particular example, the paper label stuck to the rawhide instead of the tree.
On this particular piece of saddletree cover, there is an inspectors ink stamp, which is worn and unreadable.
This company was one of the largest saddletree companies in the world, and may have produced the majority of saddletrees used for saddles made during WW1.