Noctua NF-A4x20 PWM Premium Fan

Noctua NF-A4x20 PWM Premium Fan Noctua-NF-A4X20-PWM Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO frame, the NF-A4x20 PWM is a highly optimised, premium-qualityquiet fan in size 40x20mm. The PWM version sports Noctua’s custom-designed NE-FD1 IC for fully automatic speed control via 4-pin fan headers and comes with a Low-NoiseAdaptor as well as an OmniJoinTM Adaptor Set for easy connection to proprietary fan headers. Its superb running smoothness, reference-class SSO2 bearing and Noctua’strusted premium quality make it an elite choice for the highest demands. PRODUCT SPECIFICATIONS:  Dimensions: 40x40x20 mm Mounting Hole Spacing:  32x32 mm Connector & Pin-configuration: 4-pin PWM Cable length:  20cm + 30cm NA-EC1 extension cable Bearing: SSO2 Blade Geometry: A-Series with Flow Acceleration Channels Frame Technology: AAO (Advanced Acoustic Optimisation) Rotational Speed (+/- 10%): 5000 RPM Rotational speed with L.N.A.