The contacts are mounted in parallel with the capacitor, and control the opening and closing of the circuit and the sending of the current to the ends of the primary inductor.

Also known as platinum points, the contacts open a circuit that transmits the current to the primary winding of the coil, causing the charging of the capacitor and a voltage swing which, every time the circuit is opened, transmits the spark to the spark plugs by means of a high voltage pulse.