Iria

"The ZEROtherm Zen CPU Cooler has taken the towering heatsink design to the next level. ZEROtherm has decided to add a different feature when designing the Zen CPU Cooler by adding a honeycomb design to the fins in the middle of the heatsink, which will add to the surface area and make the dissipation of the heat more effective. Not only does it have the honeycomb design in the center of it, the Zen CPU Cooler is very large, allowing it to house a 120mm fan on it's front or back side. When you have the 120mm fan installed, the temperatures are average with the other coolers in it's class, however when you decide to take the 120mm fan off, the temperatures shoot up."
____________
Source: OCC