When the Ignition switch is closed the current from the battery flows through the primary winding of the Ignition coil to the insulated fixed contact point of the contact-breaker unit. The hinged armed contact is held in contact with the fixed contact by means of a compression spring. The cam is driven at half of the engine speeding the case of the four stroke cycle engine, producing three sparks per revolution in the case of a six cylinder engine. When the contact points open the high voltage current produced by the Ignition coil is led to the rotor of the distributor by a high tension cable. An apparatus used to condense vapor, usually using cooling or pressurization is known as capacitor or condenser.