It is a so (resonance transformer) transformer with a resonance principle of the operation, by American Serb scientist Nicholas. Tesla invented in 1891, mainly used to the production of ultra high voltage and low current, high frequency AC power. The Tesla coil is composed of two groups (sometimes using three groups). Tesla coil is difficult to define, Nicola Tesla trial a large number of various coil configuration. Tesla used these coils carry out innovative experiments, such as electric lighting, fluorescence spectra, X-ray, high frequency alternating current phenomena, electrotherapy and radio transmission, transmitting and receiving radio signals.

 

All you will receive are in this picture,need you  prepare a 12V power