Features: Experience the calming effects of the Schumann Resonance with our rechargeable 7.83Hz Extremely Low Frequency Generator, to enhances your relaxation and sleep quality. Featuring 5V USB charging interfaces, this device fully charges in approximately 3 4 hours and offer over 100 hours of continuous use on a single charge, making it both efficient and convenient. for both men and women, this generator for anyone seekings improved sleep and relaxation, regardless of age or lifestyle. for use in bedrooms, offices, or any space where tranquilitys is desired, this generator help create a soothing environment conducive to rest and concentration. from ABS materials, this Schumann Resonance Generator seamlessly integrates into daily routine, providing solution for stress relief and enhanceds well being. Specifications: Materials: ABS Size:68x52x12mm/2.68x2.05x0.47inch Package Includes: 1Set Schumann Resonance Generator note: Please allow 0-1cm error due to manual measurement. make sure you not mind before bid. Due to the differences between different monitors, the picture may not reflect the actual of the item. Thank you!