"The unique design of the Nirvana NV120 PWM heatsink sees a 120mm PWM fan set within the body of the heatsink. The translucent fan blades spin at speeds of between 1800-900RPM. For a little visual flair, blue LEDs illuminate the blades. Constructed primarily of aluminum, the Nirvana NV120 PWM incorporates four 6mm diameter copper heatpipes soldered to a substantial copper base block. While many manufacturers have adopted 'exposed' heatpipe designs, Zerotherm are sticking with what works and tossing in a healthy dose of dark nickel plating."