Feature: 1. 2 in 1 Coil: Mini solid state coil, both primary and secondary are made of PCB, both toroid and coil head with integrated 6 discharge pins. High integration, cleaner and safer. 2. Music Arc Mode: When the music mode is turned on, if there is no music playing, no arc will be generated. When playing music, you will see the arc dancing, which is very ornamental. Please turn your phone volume to maximum for music mode to work properly. 3. Safe Use: In music mode, the arc size cannot exceed the 11 o'clock direction. If the knob pointer exceeds the direction of 11 o'clock, the power is too high, and the coil will stop working. Bluetooth will also disconnect automatically. You need to stop the coil and restart it. 4. Two Connection Methods: You can connect via bluetooth on your phone. Or connect the coil to your phone or computer via a 3.5mm audio cable. Both methods are valid for music mode. 5. Surprising Gift: In normal mode, you can lightly touch the arc. If your fingers feel uncomfortable, you can retract your hand. It can wow everyone and makes a really cool collectible and gift. 6. Tips: When using an audio cable to connect a smartphone to the coil, it may cause the touch screen to malfunction, which is normal. After unplugging the audio cable, the phone goes back to normal. Specification: Item Type: Bluetooth Music Coil Module KitMaterial: PCB, acrylic, aluminum alloy Voltage: 100-240V, 50/60Hz Power Output: 48V 2A Secondary Coil Diameter: Approx. 2in/51mm Maximum Arc Length: Approx. 3.93in/100mm. Package List: 1 x Host1 x Adapter2 x Secondary Coil7 x Discharge Needle4 x Small Neon Lamp1 x Toroid Note: 1. Not suitable for people with implanted electronic medical devices.2. Do not touch the secondary coil with any conductors.3. Do not use Tesla coils on metal workbenches.4. Keep away from flammable and explosive materials.5. In music mode, the arc size cannot exceed the 11 o'clock direction. If the knob pointer exceeds the direction of 11 o'clock, the power is too high, the coil will enter the protection state and stop working. Bluetooth will also disconnect automatically. You need to stop the coil and restart it. In normal mode, the frequency and arc size can be adjusted at will.