Size is as-packaged, or the diameter of loose marbles. ("D" is the diameter of round items other than marbles.)
These flexible latex rings are perfectly sized (1/4") for displaying the most common size marbles - 5/8"! They will not scratch, and their neutral color ensures they do not detract visually from the marble they are showcasing! Use them on open shelf displays to keep marbles from rolling away. Also suitable for use in display cases to make sure the marbles don't shift as you close the lid. Bag contains 100 rings.