Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO frame, the NF-A4x10 FLX is a highly optimised, premium quality quiet fan in 40x10mm size. Smooth Commutation Drive technology and Noctua’s reference class SSO2 bearings guarantee superb running smoothness and excellent long-term stability. Topped off with modular cabling, a Low-Noise Adaptor and OmniJoin Adaptor Set as well as 6 years manufacturer’s warranty, the NF-A4x10 is a premium choice for the highest demands.Flow Acceleration ChannelsThe NF-A4x10 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 and thus leads to better efficiency and lower vortex noise.Reduced motor hub sizeReduced motor hub sizeThanks to its streamlined, compact motor design, the NF-A4x10's motor hub is smaller than with conventional 4cm fans. This allows for more blade surface area and thus contributes to the NF-A4x10's superior airflow and pressure performance.AAO frameAAO frameNoctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency.Stepped Inlet DesignStepped Inlet DesignNoctua'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 and increases suction capacity, especially in space-restricted environments.Inner Surface MicrostructuresInner Surface MicrostructuresWith 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 and improved airflow and pressure efficiency.Integrated Anti-Vibration PadsIntegrated Anti-Vibration PadsIntegrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems and fan clips used on heatsinks.Smooth Commutation Drive 2Smooth Commutation Drive 2The latest version of Noctua's advanced Smooth Commutation Drive system ensures superb running smoothness by eliminating torque variations and switching noises. This makes the NF-A4x10 remarkably quiet even at very close distances.SSO2 BearingSSO2 BearingThe NF-A4x10 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 and durability.Low-Noise Adaptor for full flexibilityLow-Noise Adaptor for full flexibilityThe NF-A4x10 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 and Polarity Protection3 to 2-pin Adaptor and Polarity ProtectionThe NF-A4x10 comes with an adaptor from 3-pin Molex to the 2-pin connectors used on many graphics cards or network and storage devices. An integrated diode provides polarity protection on 2-pin connections.OmniJoin™ Adaptor SetOmniJoin™ Adaptor SetMany devices featuring 40mm fans use proprietary fan headers, so the NF-A4x10 comes with Noctua's OmniJoin™ adaptor set. Just cut the original fan's cable, fix it to the adaptor using the supplied 3M Scotchlok™ connectors and you can plug the NF-A4x10 to proprietary fan headers!Extensive cabling optionsExtensive cabling optionsThe fan's 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.6-year manufacturer’s warranty6-year manufacturer’s warrantyNoctua fans are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the NF-A4x10 features an MTTF of more than 150.000 hours rating and comes with a full 6-year manufacturer's warranty.