The SMDTB14 is an optimized product that simplifies the complex procedures of previous versions. The upgraded SMDTB14 uses three buttons to set parameters. It adds four audio signal outputs, increasing signal expansion capability by four times. It features amplifiers, overcurrent and overvoltage protection, and high- low-temperature circuitry. It also includes a robust acrylic housing. Only beneficial sine wave signals are retained, removing square waves, triangle waves, and sawtooth waves that are only suitable for laboratory use. The 7.83 Hz resonance is suitable for various applications, such as overall health, improved productivity, stress relief, and aiding sleep. For more information, search for " generator" in your browser. Features: Outputs the beneficial 7.83Hz wave, adjustable from 0.01Hz to 9999Hz. Employs a high-speed for pure sine wave generation. Includes four 3.5mm audio outputs with amplifiers. Encased in a , transparent acrylic shell. Compact and design for easy portability. Specifications: 1. Working Voltage: DC 5V 2. Working Current: 15-30MA 3. Power Interface: Type-C (supports TYPE-C to TYPE-C power supply) 4. Default Frequency: 7.83Hz 5. Frequency Adjustment Range: 0.01Hz~9999Hz Pure Sine Wave 6. Signal Voltage Amplitude: 3V 7. Dimensions: 104*66*18MM Color: White Material: plastic Package Contents: 1*Signal Generator 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.