When you sit down and touch the chair back, a lamp which is mounted under the chair lights up. The stronger you lean back, the brighter the light becomes. This should be a very simple and easy to learn principle, that invites you to play with it.

Having reached a certain level of brightness, the light suddenly flashes up and you hear the sound of a blow. Now the light is off and you can see or smell a little smoke coming up from under the chair. The system won’t work any more for a few minutes making you believe you destroyed it.