The operating principle of the machine is based on two counter-rotating discs made of insulating material.<br> Each disc has several metal segments attached to it, called sectors.<br> As the sectors pass, they induce a fee imbalance on another.<br> This imbalance is drained to the collecting electrodes.<br> 1. 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*10.5cm<br> Material:Wood + metal<br> colour:Silver<br> Package Contents:<br> 1 * Electrostatic Generator<br> Only the above package content, other products are not included.<br> Note: Light 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.