Hydro Series H70 CORE builds on the legacy of the original H70 cooler, with one key difference: you supply your own fans. If you've already built a high-performance PC system (or three), you probably have a few extra 120 mm fans lying around. Or, you might just want to choose your own fans. Either way, the H70 CORE gives you the freedom to fully customize your cooling performance. The physics are simple: larger radiators have more surface area, and more surface area means more efficient heat transfer. The H70 CORE radiator is twice as thick as the standard radiator to provide excellent cooling potential.