Caster cups help protect your hardwood flooring or carpeting from indentations from the weight of the piano.
These piano caster cups are made of hardwood with an ebony (black) finish. They measure 3-1/2" outside diameter and 2" tapering to 1-3/4" inside diameter with a felt bottom to protect your flooring.
Check out our blog for help in choosing the right caster cups for you:
https://intunepianosupply.com/blogs/piano-basics/what-are-piano-caster-cups-and-why-are-they-important