A radiator is connected to channels running through the engine and cylinder head, through which a liquid (coolant) is pumped. This liquid is typically a half-and-half mixture of water and ethylene glycol or propylene glycol (with a small amount of corrosion inhibitor) known as antifreeze. The radiator transfers the heat from the fluid inside to the air outside, thereby cooling the engine. Radiators are generally mounted in a position where they will receive airflow from the forward movement of the vehicle such as behind the grill.