You receive: This product includes a resonance generator, an acrylic case with a small magnet, and a USB data cable. Note: The acrylic case may have a slight odor, which can dissipate when placed in sunlight or a well-ventilated area for 2 to 3 days. It is recommended to remove the protective film before use. This device generates low-frequency electromagnetic waves and requires the use of headphones. Adjustable frequency: 0.01 to 100,000 Hz adjustable range. The sine wave generator allows customizable settings for efficiency and personalization. Default frequency is 7.83 Hz, with additional options including 174 Hz, 285 Hz, 396 Hz, 417 Hz, 528 Hz, 639 Hz, 741 Hz, 852 Hz, and 963 Hz. Multiple waveforms: The audio generator supports sine wave, square wave, and reverse square wave outputs, suitable for various applications in environments such as laboratories and studios. Promotes relaxation: The adjustable resonance generator emits sine waves to help create a calming environment, supporting improved mental state and overall well-being. Makes a thoughtful gift for holidays such as birthdays and Christmas. Portable design: The sound generator measures approximately 5.9 x 5.5 x 1.2 inches. The acrylic case measures approximately 6.2 x 5.8 x 1.5 inches, providing secure coverage. Compact size and USB-powered operation allow for easy portability and use at home, work, or during travel. Stable performance: Sine wave generator with a default frequency of 7.83 Hz. Sine wave voltage amplitude is 3V; square wave voltage amplitude is 5V, ensuring stable and accurate signal output. Wide application: Suitable for environments requiring signal generation and frequency adjustment, including electronic testing, equipment calibration, and scientific experiments. Specifications: Frequency range: 0.01 to 300,000 Hz Default frequency: 7.83 Hz Power supply: 5V Sine wave voltage amplitude: 3V Square wave voltage amplitude: 5V Color: As shown Material: Metal + Acrylic Package contents: 1 x Adjustable sine wave resonance generator 1 x Acrylic case 1 x USB data cable Note: Light reflection and display differences may cause slight variations between the item color in images and the actual product. Measurement error allowance is +/- 1-3 cm.