Noctua 200mm Nf-a20 Flx 800rpm Fan NF-A20-FLX, Dimensions: 200 x 200 x 30 mm, Mounting hole spacing: 154x154, 110x180, 170x170 mm, Connector: 3-Pin, Bearing: SSO2, Blade Geometry: A-Series with Flow Acceleration Channels, Frame Technology: AAO (Advanced Acoustic Optimisation), Rotational Speed (±10%): 800 RPM, Rotational Speed with L.N.A. (±10%): 550 RPM, Airflow: 86.4 CFM The NF-A20 is a highly optimised, premium quality quiet 200mm fan. Featuring an AAO (Advanced Acoustic Optimisation) standard frame as well as sophisticated aerodynamic design measures such as Flow Acceleration Channe