Noctua NF-B9 redux-1600, 3-Pin, High Performance Cooling Fan with 1600RPM (92mm, Grey) The redox product line reissues some of Noctuid's most popular, award-winning models. Noctuid's signature Vortex-Control Notches split up trailing edge vortices and thus spread the fan's noise emission over a wider range of frequencies. This measure makes the fan sound more pleasant to the human ear. Reducing critical rotor stator interaction, Beveled Blade Tips permit to combine extended leading edges and a higher blade surface area with quieter operation and thus form a cornerstone of the fan's outstanding efficiency. The latest version of Noctuid's advanced Smooth Commutation Drive system ensures superb running smoothness by eliminating torque variations and switching noises. This makes the fan remarkably quiet even at very close distance. Combining the proven concept of hydrodynamic bearings with an add'l magnet that supports the self-stabilization of the rotor axis, Noctuid's time-tested SSO-Bearing tech Users can choose from Noctuid's wide range of optional accessories such as anti-vibration mounts, Low-Noise-Adaptors, y-cables, 3:4 pin adaptors or extension cables to upgrade redox edition fans according to their individual needs.