Advanced Wireless Technology: Experience the magic of electromagnetic transmission with this Coil Speaker, designed to demonstrate wireless power transfer through its captivating arc plasma display. Bluetooth Compatibility: Easily connect your devices via Bluetooth to integrate sound with the visual spectacle of the plasma arcs, making science experiments more engaging and educational. Perfect Educational Tool: Ideal for classrooms, science fairs, and home experiments, this loudspeaker helps illustrate the principles of voltage and current interactions in an exciting and visually appealing way. Safe and Portable: Built with safety in mind, this compact device is perfect for demonstrating advanced scientific in a safe and controlled environment. Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. voltage: AC220V Input voltage: 48V Music transmission mode: Bluetooth, AUX audio input Arc length: 0-8cm Discharge frequency: 5-50hz (Fast Charging mode) Colour:Black Material:Acrylic Notes: 1. Do not approach and items during operation 2. Avoid arcs hitting other electronic devices 3. Be careful not to be poked by the discharge needle 4. must use under adult supervision 5. Do not place objects on the host panel to avoid high temperature damage to the shell Due to different batches, there may be differences in product appearance and printed text, which not affect use Package Contents: 1 * Coil Speaker 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.