The Noiseblocker NB-BlackSilentFan XL2 120mmx25mm Ultra Quiet Fan, manufactured by Noiseblocker, Germany"s quietest fan manufacturer, the BlackSilentFan series features extraordinary life spans and near silent operation. Using the NB-Longlife advanced sleeve bearing and matched with the NB-EKA drive, the BlackSilentFan series runs more than double the life of normal sleeve bearings in operates so quietly you"ll forget they are running. These fans are silent performance at high value!