Noctua NF-A4x 10 FLX 40mm x 10mm Low Noise Fan Noctua's first ever 40mm fan is so features packed there isn't enough room to mention them all here. Read on to find out more. Featuring advanced aerodynamic design measures such as Flow Acceleration Channels & Noctua's AAO frame, the NF-A4x 10 FLX is a highly optimised, premium quality quiet fan in 40x 10mm size. Smooth Commutation Drive technology & Noctua's reference class SSO2 bearings guarantee superb running smoothness & excellent long-term stability. Topped off with modular cabling, a Low-Noise Adaptor & Omni Join Adaptor Set as well as six years manufacturer's warranty, the NF-A4x 10 is a premium choice for the highest demands. Features 40 x 10mm quiet PC cooling fan Noise level from 12.9 d B (A) Feature packed Perfect for propitiatory cooling Flow Acceleration Channels The NF-A4x 10 impeller features suction side Flow Acceleration Channels. By speeding up the airflow at the crucial outer blade regions, this measure reduces suction side flow separation & thus leads to better efficiency & lower vortex noise. More info. Reduced Motor Hub Size Thanks to its streamlined, compact motor design, the NF-A4x 10's motor hub is smaller than with conventional 4cm fans. This allows for more blade surface area & thus contributes to the NF-A4x 10's superior airflow & pressure performance. AAO Frame Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design & Inner Surface Microstructures, both of which further refine the fans performance/noise efficiency. More info Stepped Inlet Design Noctua's Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment & increases suction capacity, especially in space restricted environments. More info Inner Surface Microstructures With the tips of the fan blades ploughing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed, which results in reduced blade passing noise & enhanced airflow & pressure efficiency. More info Integrated Anti-Vibration Pads Integrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems & fan clips used on heatsinks. Smooth Commutation Drive 2 The latest version of Noctua's advanced Smooth Commutation Drive system ensures superb running smoothness by eliminating torque variations & switching noises. This makes the NF-A4x 10 remarkably quiet even at very close distance. More info SSO2 Bearing The NF-A4x 10 features the further optimised second generation of Noctua's renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision & durability. More info Low-Noise Adaptor for full flexibility The NF-A4x 10 FLX (Flexibility) is supplied with a Low-Noise Adaptor (L.N.A.) that reduces the maximum fan speed from 4500 to 3700rpm so that it can be fine-tuned for superior airflow or maximum quietness. 3 to 2-pin Adaptor & Polarity Protection The NF-A4x 10 comes with an adaptor from 3-pin Molex to the 2-pin connectors used on many graphics cards or network & storage devices. An integrated diode provides polarity protection on 2-pin connections. Omni Join Adaptor Set Many devices featuring 40mm fans use proprietary fan headers, so the NF-A4x 10 comes with Noctua's Omni Join Adaptor Set. Just cut the original fans cable, fix it to the adaptor using the supplied 3M Scotchlok connectors & you can plug the NF-A4x 10 to proprietary fan headers! More info Extensive Cabling Options The fans short 20cm primary cable minimises cable clutter in typical applications while the supplied 30cm extension provides extended reach when necessary. Both cables are fully sleeved. Six years manufacturer's warranty Noctua fans are renowned for their impeccable quality & outstanding longevity. Like all Noctua fans, the NF-A4x 10 features an MTBF of more than 150, 000 hours rating & comes with a full six years manufacturer's warranty.