The radiator is usually based on one of these two designs: cross flow or down flow. In a cross-flow radiator (Figure 12–39), coolant enters on one side, travels through tubes, and collects on the opposite side. In a down-flow radiator, coolant enters the top of the radiator and is drawn downward by gravity. Cross-flow radiators are seen most often on late-model cars because all the coolant flows through the fan airstream, and the design allows for lower hood profiles on body designs.