"A promising looking tower heatsink, the Glacialtech Alaska CPU cooler sets itself apart with the use of perforated aluminum cooling fins, a pseudo-honeycomb cross sectional fin geometry and six 6mm diameter copper heatpipes tightly packed behind an integral nickel-plated copper heatspreader. The dozens of 2mm diameter perforations dot each of the 40 or so aluminum fins on the Alaska heatsink and function as a pathway for air pressure to equalize between the different cooling fins. Glacialtech call this the "breathing effect"."