When I was little, my dad worked, Mom stayed home withthe kids, and made some extra money by ironing for a nurse around the corner. That's back when nurses wore pressed white uniforms, and iron's didn't steam. She'd use these and sprinkled the uniforms, roll them up, then stick them in the freezer.
My laundry room has a bottle with that type of cap for decoration, a couple of wire rug beaters, a metal iron that used to be put in the fire to get hot (before my time) an old washboard, and the wringer from an old wringer washing machine, all for decoration. Next to my Maytags and uprght freezer!