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Noctua NF-A4x20 FLX fan - 40mm [NF-A4x20 FLX]

Noctua NF-A4x20 FLX fan - 40mm
Noctua NF-A4x20 FLX fan - 40mm
Noctua NF-A4x20 FLX fan - 40mm
Noctua NF-A4x20 FLX fan - 40mm


The NF-A4x20 FLX is a high-performance silent 40 x 20 mm fan in premium quality, based on Noctua's AAO frame system and advanced aerodynamic design measures such as Flow Acceleration Channels.
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  20+ Available for Delivery in 2-3 Days
  FREE UK/EU DELIVERY over £500+
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EAN: 9010018100112
Warranty: 12 Months
£16.73 inc VAT
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  • USD $21.66 *


The Smooth Commutation Drive technology and the SSO2 reference class bearing guarantee superbe stability and excellent long-term stability. Modular cabling, a low-noise adapter, the OmniJoin adapter set and a 6-year manufacturing guarantee make the NF-A4x20 FLX a premium solution for the highest demands.
The features of the Noctua NF-A4x20 FLX at a glance:

Stylish brown makes for a noble look
Premium fan with aerodynamic design
Extremely low noise emission of max. 14.9 dB (A)
High static pressure of up to 2.26 mm H2O
High flow rate of max. 9.4 m³ / h
Connection via 3-pin PWM
Very high life expectancy of over 150,000 hours
Long warranty: 6 years
Small premium fan from Noctua

The impeller of the NF-A4x20 FLX is equipped on the suction side with so-called flow acceleration channels. By accelerating the air flow in the critical outer regions of the fan blades, suction-side vortex detachments are reduced, resulting in higher efficiency and lower turbulence-induced noise emission. Thanks to an optimized, compact motor design, the hub area of the NF-A4x20 FLX is significantly smaller than conventional 4cm fans. This enabled a larger blade area to be achieved, which contributes to the superior printing and conveying performance of the NF-A4x20 FLX. By a double construction depth compared to the NF-A4x10, the pressure and delivery capacity was increased, making the fan perfect for applications with higher air resistance.

Noctua's Advanced Acoustic Optimization (AOO) frames have built-in vibration buffers, stepped inlet design, and internal surface microstructures that provide even better performance / noise efficiency. The stepped inlet area of the Stepped Inlet design creates more turbulence in the inflow. This facilitates the transition from laminar to turbulent flow, which is better adhered to the frame (flow attachment) and thus, especially with limited suction area, increases the suction capacity of the fan.

The microstructure inside the inner surface (Inner Surface Microstructures) creates a boundary layer through which the tips of the fan blades move. This reduces the current dissipation from the suction side of the blade tips, which results in a considerable reduction in the rotary sound as well as an increase in the pressure and air flow efficiency. The anti-vibration pads made from extra-soft silicone reduce the transmission of minimal vibrations and are compatible with all standard screws as well as standard mounting systems or fan brackets used with CPU coolers.

The latest, advanced version of Noctur's SCD drive system ensures excellent run-down due to the elimination of torque fluctuations and switching noises. This makes the NF-A4x20 FLX itself amazingly quiet at close range. The NF-A4x20 FLX is equipped with the further optimized second generation Noctua's proven SSO bearing system. With SSO2, the backside magnet is closer to the fan axis, resulting in even better stabilization resulting in further improved precision and durability.

The NF-A4x20 FLX (Flexibility) can be throttled from 5,000 to 4,400 rpm using the included low-noise adapters, thus enabling fine tuning for maximum flow or maximum running stability. If this is not enough, the enclosed Ultra-Low-Noise adapter can limit the fan to 3,700 rpm. The NF-A4x20 FLX is delivered with an adapter from 3-pin Molex to 4-pin connections, which allows a direct connection to the power supply.

Because many devices that use 40mm fans have proprietary fan connectors, the NF-A4x20 FLX is shipped with Noctua's OmniJoin adapter set. Simply cut off the cable of the original fan, attach it with the included 3M Scotchlok ?? Terminals on the adapter and you can already operate the NF-A4x20 FLX at proprietary connections! While the 20 cm short primary cable in typical applications helps to avoid cables, the supplied 30 cm extension provides extra range for all cases. Both cables are completely jacketed.

Noctuas fans are known for their makellose quality and outstanding longevity. Like all Noctua fans, the NF-A4x20 FLX has an MTBF specification of over 150,000 hours and comes with a full six-year manufacturing warranty.

Technical specifications:
Format: 40 x 40 x 20 mm
Storage Type: SSO2-Bearing
Leaf Geometry: A Series with Flow Acceleration Channels
Rotational. (+/- 10%): 5,000 rpm
Rotational. With L.N.A. (+/- 10%): 4.400 rpm
Rotational. With U.L.N.A. (+/- 10%): 3,700 rpm
Flow rate: 9,4 m³ / h
Volume flow with L.N.A .: 8.3 m³ / h
Volume flow with U.L.N. .: 6.9 m³ / h
Sound Emission: 14.9 dB (A)
Sound development with L.N.A .: 12.2 dB (A)
Noise reduction with U.L.N.A .: 8.5 dB (A)
Static pressure: 2.26 mm H2O
Static pressure with L.N.A .: 1.75 mm H2O
Static pressure with U.L.N. .: 1.23 mm H2O
Max. Power consumption: 0.6 W
Max. Current: 0.05 A
Operating voltage: 12 V
MTBF:> 150,000 h
Connection: 3-pin

Low-Noise Adapter (L.N.A.)
Ultra Low Noise Adapter (U.L.N.A.)
4-pin Y-cable
30 cm cable extension
NA-AV3 Anti-vibration mountings
4 fan screws

Manufacturer Warranty 6 years


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