The Multiframe S series made by (((Noiseblocker))), which is generally recognised as the reference standard, is the first fan with a vibration-free fan frame and incorporates numerous other improvements, so that it is superior to standard fans in almost all aspects.In conjunction with the unique (((Noiseblocker))) technology, our almost noise-free NB-NanoSLI bearing and the NB-EKAPlus II drive, the NB-Multiframe S series currently represents the best that German engineering expertise has to offer. Quality you can rely on! Specification:- Dimensions: 120x120x25mm- Noise Level: 27dbA- RPM: 1800rpm