Noctua NF-A15 PWM, 4-Pin Premium Cooling Fan (140mm, Brown) Award-winning 140x25mm A-series fan with Flow Acceleration Channels and Advanced Acoustic Optimisation frame for superior quiet cooling performance 150mm wide round frame design with 120mm standard mounting holes (105mm spacing) is ideal for use on high-end CPU coolers such as Noctuas NH-D15(S) or NH-U14S series 4-pin PWM version for automatic speed control via 4-pin PWM fan headers, broad 300-1200rpm speed range (900rpm max. with supplied Low-Noise Adaptor) Includes anti-vibration mounts, fan screws, Low-Noise Adaptor, extension cable and y-cable for running two PWM fans on the same header Trusted Noctua quality with premium-grade SSO2 bearing and more than 150.000 hours MTTF, backed up with 6-year manufacturers warranty