Singing Bowl
The singing bowl is a type of bell that vibrates and produces a rich, deep tone when played. The sound of the bowl has calming effects and provides one with clarity and peace of mind.
Tibetan singing bowls are said to promote relaxation and offer powerful healing properties. It also can be used for meditation, yoga, and reiki sessions.
In addition, some wellness practitioners (including music therapists, massage therapists, and yoga therapists) use Zenbless singing bowls during treatment.

Mantra on singing bowl
A mantra is a sacred utterance or word in Sanskrit believed by practitioners to have religious, magical or spiritual powers.
In other words, a mantra is an instrument of the mind¡ªa powerful sound or vibration that you can use to enter a deep state of meditation.