Cooling today's high-performance PCs is a complex task, and a single fan design can't meet every need. The fan you use to pull hot air out of your case might not be the best fan to mount flush against a heatsink or radiator.
Static pressure is the measure of how well a fan can push air in this type of highly restrictive environment, and this is where the SP120 excels. It's an ideal solution for radiator and heatsink use, as well as drive bay intakes, and other locations where you're mounting a fan directly adjacent to a heat source.
CORSAIR Air Series SP120 Quiet Edition High Static Pressure - case fan
2 (specifications are for single item)
Mounting screws for case fans, 3 replaceable colour rings