Noctua NF-A4x20-FLX Case Fan, 40 x 40 x 20 mm, 3-pin, Beige/Brown

The Noctua NF-A4x20-FLX is a 40x20 mm case fan designed for applications requiring reliable cooling in space-constrained enclosures. Its dimensions make it suitable for small-form-factor (SFF) builds, 1U servers, and other compact hardware where standard-sized fans cannot be installed. The fan generates focused airflow with high static pressure, a characteristic beneficial for moving air through dense components or restrictive vents. It operates via a standard 3-pin fan header, allowing for voltage-based speed control through a compatible motherboard or fan controller.

This fan is constructed around Noctua's SSO2 bearing, a self-stabilizing oil-pressure system engineered for operational stability and an extended lifespan. At its maximum rotational speed of 5000 RPM, it produces an airflow of 5.53 CFM and 2.26 mmH2O of static pressure. The package includes a Low-Noise Adaptor (L.N.A.) and an Ultra-Low-Noise Adaptor (U.L.N.A.), which can be used to reduce the fan's speed to 3700 RPM for quieter operation. Also supplied are anti-vibration mounts, a 30 cm extension cable, and an OmniJoin adaptor set for versatile connectivity.

• Compact 40x20 mm frame for tight spaces
• Reaches a maximum speed of 5000 RPM
• Features an SSO2 bearing for long-term reliability
• Includes adapters to reduce fan speed and noise
• Supplied with anti-vibration mounts and a 30 cm extension cable
• Uses a standard 3-pin connector for power