[Endless Fun] This music Tesla has the function of wireless transmission and loudspeaker, can light gaseous tube and kind of bubbles. The arc of the wireless transmission experiment model can be touched at will, with only a slight feeling and temperature, use it with confidence. It is a perfect teaching tool to spark students' interest of science, also a great gift. It's also a cool piece of art even just stands on your desk. [Long Arc Mode & Music Mode] Long arc mode and music mode: Long arc mode releases-lightning at a fixed frequency. When the knob is turned to medium power, the-lightning can be touched, and you will only feel a little tingling. Music mode: Connect to the device via Bluetooth, it can play square wave music, and lightning-energy is concentrated in the cluster. You can see the arc of Tesla coil beating to the music, it will present an amazing sparkling melody. [Small Body with Strong Energy] With complicated circuit design and an upgraded larger top booster coil, the optimized Tesla coil lightning-arc is long and thick, which has amazing energy. Turn the voice slowly to avoid big shock by the arc sound. Before power on, make sure to turn the 2 knobs counter clockwise to the end, just avoid sudden loud sound to scare you. [Easy to Use] The wireless transmission experiment model requires no audio cable connection, easy to operate, just tighten the discharge pin, turn down the power and frequency, and plug in, it will present an amazing sparkling melody. Tesla modules can be placed horizontally or vertically, depending on your preference. It's absolutely a magic for kids even for adults, they will become fascinated for this Tesla coil. Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Voltage:AC100-240V Colour:Black Material:Metal Package Contents: 1 * Bluetooth Music Coil 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.