Figure 4 reveals the front of the heatsink, where the 120 mm fan will be installed.

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Figure 4: Front view

Figure 5 presents the side of the heatsink. Notice that the fins are folded, creating a closed panel.

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Figure 5: Side view

Figure 6 shows the back of the heatsink. Due to the shape of the fins and the extended closed surface, the area for airflow exit is smaller than the front intake area.

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Figure 6: Rear view

The top of the heatsink is shown in Figure 7. Note that the fins have a texture in order to create turbulence that improves the heat transfer.

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Figure 7: Top view