FOR coils produce high-temperature and high-pressure plasmas, can , wirelessly transmit electricity, illuminate fluorescent lamps, and have wonderful arcs. There are many fun and very interesting scientific experiments. FOR Coil is a transformer that operates on the principle of resonance (resonance transformer). Input voltage: 9-12V, can be started with 9V battery, but if there is an arc, the working voltage needs 12V. TYPE: B-Bulk parts, assembly required Material: PCB,Electronic Components colour: Multicolor Package Contents: 1 x BD243 Mini FOR Coil Kit 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.