This is either a Hat Holder or a suspenders holder.
Photo included showing envelope IS NOT THIS LISTING - I include here as it describes that this item is a Hat Holder.
But the piece for sale here (rest of the pictures) has a metal ring on top that says “SWEET-ORR UNION MADE OVERALLS” on one side and “SWEET-ORR UNION MADE TROUSERS” on the other side.
4.5 inches tall
1 inch wide
Black leather
Copper colored spring clip with logo