The Bosch Ignition Coil Service Kit - 140702 is a comprehensive kit designed to service the ignition coils of a car. It includes three essential components: an ignition coil, a spark plug, and a spark plug wire. These components work together to ignite the fuel and air mixture in the engine, providing the necessary power to start the car. The ignition coil is responsible for converting the low voltage from the battery into high voltage necessary for the spark plugs to create a spark. The spark plug is responsible for igniting the fuel and air mixture, while the spark plug wire connects the spark plug to the ignition coil. This kit is essential for maintaining the proper functioning of the ignition system, ensuring smooth and efficient performance of the car.