In Buddhist and Hindu traditions, OM is considered to be the primordial tone of the universe, which the basis of all things that are formed. 136.1 Hz is a frequency that resonates with the Earth and creates a calming and balanced sensation. Earth is believed to be the Heart Chakra of the Universe. Using weighted tuning forks can balance your specific chakras, auric field, mental & emotional bodies, among other things. Simply strike the weighted tuning fork using the mallet to create the sound therapy you desire and place the stem on any part of your body. To enhance your healing, you can place a crystal between your body and the stem of fork for the ultimate experience. Each weighted tuning fork comes with a mallet and bag. Approximate measurements: 8 inches