Prayer/Rosary/Guru/Sumeru Beads

Some examples...

"Historically, people the world over have enjoyed the assistance of a mala, rosary, or prayer beads, usually accompanied by the invocation of a divine name. Across religions, this powerful rite is believed to help guide the believer towards the path of self-realization and virtue. All sacred traditions hold that human beings are innately divine. Spirituality helps to recover this true status, and the use of malas, rosaries, and prayer beads across different faiths has this goal as its particular focus."

"Many mala will have a 109th bead which is variously called the guru, Sumeru, bindu, stupa, or mother bead. It is often larger or of a distinctive material or colour. In some Buddhist traditions, the mother bead represents Amitabha or Avalokitesvara. Guru beads are often drilled with two holes. One hole is of the same diameter as on the other beads and passes all the way through the bead, and the other hole is of a larger diameter but only goes half-way through the bead, meeting the first hole at a right angle. This allows the two ends of the cord to enter from the sides of the guru bead and then exit out the bottom together. Particularly when a tassel is not present, a small decorative conical bead may additionally be fitted where the cord exits the guru bead."

Sources:

https://dharma-beads.net/
https://en.wikipedia.org/wiki/Japamala