Consolidate your memory while you sleep Stimulates the brain into deep sleep Suitable for improving inspiration when thinking Product size is compact and easy to carry Suitable for stabilizing the mind while meditating Schumann wave generator, we call it wave generator. We usually joke about it as a metaphysical wave generator. It is essentially an extremely low frequency (ELF) electromagnetic wave. According to the multiplication of the speed of light wavelength by frequency, the wavelength of electromagnetic waves at 7.83HZ is 38000 kilometers, which is very close to the well-known circumference of the Earth of 40000 kilometers. In fact, waves are an inherent property of geophysical characteristics, forming an electromagnetic resonance cavity on the surface and ionosphere. 7.83HZ is the natural frequency of this resonance cavity, and when emitted at such a frequency, electromagnetic waves will form standing waves in Earth's space, Will endure earthquakes for a long time. It is normal for each person to experience different results Colour:black Material:plastic Size: 10 x 10 x 1.8cm Package Contents: 1 x Host 1 x Type c cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.