The operating principle of the machine is based on two counter-rotating discs made of insulating material.Each disc has several metal segments attached to it, called sectors.As the sectors pass, they induce a fee imbalance on another.This imbalance is drained to the collecting electrodes.1.<br> Set the gaps between the two electrodes to about 1-2 inches.<br> 2. Turn the handle slowly first and increase the rotation.<br> 3. Once the voltage of the capacitor is enough to overcome electrostatic breakdown at the electrodes, discharge will take place and spark is seen or heard.<br> size:33*105cmMaterial:Wood + metalcolour:SilverPackage Contents:1 * Electrostatic GeneratorOnly the above package content, other products are not included.Note:<br> Light and different displays may cause the color of the item in the picture a little different from the real thing.<br> The measurement allowed error is +/- 1-3cm.<br> Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store