The captive bead or ball fits into a small opening in the circle of the ring. The bead is slightly larger than this opening and has small indentations or depressions that correspond to the ring’s end-points so that it may fit snugly against them, thus completing the circuit of the ring.
Also, how do you open a captive bead?
Use the ball grabber tool to grip the captive bead with its indentations on either side. Hold the ring steady with your free hand and push the captive bead into the open segment of the ring. The captive bead should pop into place.