Features: 1.High Stability: This Schumann wave generator is made from highly stable pulse chip, accuracy correction capacitance, and accuracy multiloop adjustable resistor. 2.Physical Relaxation: This ultra low frequency pulse generator is good for people's physical and mental relaxation, improve the body's perception of sound and images. 3.Pressure Relief: This 7.83HZ pulse generator contributes to improve work efficiency and reduce mental stress. 4.Easy to Use: This ultra low frequency pulse generator with Type C interface is easy to use. and it features high accuracy and stability. 5.Perfect Gift: Schumann wave generator is perfect gift for friends and family that suffer from insomnia and mental stress. specification:Item Type: Schumann Wave Generator Material: Printed Circuit Board Output: 7.83Hz Pulse Squared Wave Interface: Type C PackageList:1 x SchumannWaveGenerator 1 x USB Cable