Thats my new tuning fork!
You bang it with a stick, it vibrates / resonates intensely and you place the base against your solar-plexus, or your forehead, or your temple, or knees / elbows.
At 128hz, some of us believe it shatters parasites inside your body which are known to make you more prone to illness...
I also using a Tibetan singing bowl for healing frequencies too.
Changed my life.