---
product_id: 270153121
title: "Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown)"
brand: "noctua"
price: "€ 45.64"
currency: EUR
in_stock: true
reviews_count: 6
category: "Noctua"
url: https://www.desertcart.hr/products/270153121-noctua-nf-a4x20-flx-premium-quiet-fan-3-pin-40x20mm
store_origin: HR
region: Croatia
---

# 3-speed 3700-5000 RPM control 40x40x20mm compact size Ultra-quiet max 14.9 dB(A) Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown)

**Brand:** noctua
**Price:** € 45.64
**Availability:** ✅ In Stock

## Summary

> 🛠️ Upgrade your gear with the silent powerhouse that keeps your tech cool and your focus sharper.

## Quick Answers

- **What is this?** Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) by noctua
- **How much does it cost?** € 45.64 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/270153121-noctua-nf-a4x20-flx-premium-quiet-fan-3-pin-40x20mm)

## Best For

- noctua enthusiasts

## Why This Product

- Trusted noctua brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Built to Last:** Premium SSO2 bearing ensures ultra-smooth operation and an impressive >150,000 hours MTTF for long-term reliability.
- • **Whisper-Quiet Cooling:** Experience near-silent airflow with industry-leading 14.9 dB(A) noise levels—because your workspace deserves peace.
- • **Precision Aerodynamics:** Flow Acceleration Channels and AAO frame optimize airflow for superior cooling efficiency in tight 1U and compact setups.
- • **Plug & Play Flexibility:** Includes OmniJoin™ Adaptor Set for seamless compatibility with proprietary fan headers—upgrade without hassle.
- • **Versatile Speed Control:** Three adjustable RPM settings (3700/4400/5000) via Low-Noise Adaptors let you tailor performance to your exact needs.

## Overview

The Noctua NF-A4x20 FLX is a premium 40x40x20mm quiet fan designed for compact devices like network switches and NAS units. Featuring advanced aerodynamic design with Flow Acceleration Channels and an AAO frame, it delivers efficient cooling at ultra-low noise levels (max 14.9 dB(A)). With three adjustable speeds (3700-5000 RPM) and a 3-pin connector plus OmniJoin™ adaptors, it offers versatile, easy installation and long-lasting performance backed by a >150,000 hour MTTF rating.

## Description

Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and Noctua’s AAO frame, the NF-A4x20 is a highly optimised, premium-quality quiet fan in size 40x20mm. The FLX version provides 5000/4400/3700rpm speed settings via the supplied Low-Noise Adaptors and includes the OmniJoin™ Adaptor Set for easy connection to proprietary fan headers. Its superb running smoothness, reference-class SSO2 bearing and Noctua’s trusted premium quality make it an elite choice for the highest demands.

Review: Amazing silent fan - I order two silent fans and replace a very loud original fans for network switch. Amazing performance no sound at all.
Review: Perfect for noisy TP-Link Switches - I bought a new TP-Link Switch and it was ridiculously noisy. I mean, I get that its supposed to live in a server room but surely they could've done something to tone it down a bit. Two of these to replace the ones inside the switch have made it almost silent while still providing sufficient airflow.

## Features

- Premium quiet fan, 40x40x20 mm, 12V, 3-pin Molex, 5000/4400/370 RPM, max. 14.9 dB(A), >150,000 h MTTF
- Award-winning A-series design with Flow Acceleration Channels and Advanced Acoustic Optimisation frame for superior quiet cooling performance
- 40x20mm size ideal for 1U applications or replacing fans in network and storage equipment (routers, switches, NAS etc.) or other devices such as DVRs

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B071J8CZP9 |
| Best Sellers Rank | #12,961 in Computers ( See Top 100 in Computers ) #79 in Computer Case Fans |
| Brand | Noctua |
| Brand Name | Noctua |
| Compatible Devices | Desktop, Laptop |
| Compatible devices | Desktop, Laptop |
| Cooling Method | Air |
| Cooling method | Air |
| Customer Reviews | 4.8 out of 5 stars 2,490 Reviews |
| Global Trade Identification Number | 09010018100112 |
| Item Dimensions L x W x H | 20L x 40W x 40H millimeters |
| Item Weight | 50 Grams |
| Manufacturer | Noctua |
| Material Type | Fibre-glass reinforced PBT |
| Maximum Rotational Speed | 3500 RPM |
| Model | NF-A4x20 FLX |
| Noise Level | 14.9 Decibels |
| Number of Items | 1 |
| Part Number | NF-A4x20 FLX |
| Power Connector Type | 3-Pin |
| Power connector type | 3-Pin |
| Product dimensions | 20L x 40W x 40H millimeters |
| Unit Count | 1.0 Count |
| Voltage | 12 Volts |

## Product Details

- **Brand:** Noctua
- **Cooling method:** Air
- **Power connector type:** 3-Pin
- **Product dimensions:** 20L x 40W x 40H millimeters
- **Voltage:** 12 Volts

## Images

![Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Image 1](https://m.media-amazon.com/images/I/71lyRpVR4OL.jpg)
![Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Image 2](https://m.media-amazon.com/images/I/81abh0+LmWL.jpg)
![Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Image 3](https://m.media-amazon.com/images/I/71NYZ3JQcOL.jpg)
![Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Image 4](https://m.media-amazon.com/images/I/71Ywc8LceeL.jpg)
![Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown) - Image 5](https://m.media-amazon.com/images/I/61xqdXxj1uL.jpg)

## Available Options

This product comes in different **Size, Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Amazing silent fan
*by R***X on 12 November 2022*

I order two silent fans and replace a very loud original fans for network switch. Amazing performance no sound at all.

### ⭐⭐⭐⭐⭐ Perfect for noisy TP-Link Switches
*by D***N on 2 February 2022*

I bought a new TP-Link Switch and it was ridiculously noisy. I mean, I get that its supposed to live in a server room but surely they could've done something to tone it down a bit. Two of these to replace the ones inside the switch have made it almost silent while still providing sufficient airflow.

### ⭐⭐⭐⭐⭐ Just Wow
*by S***H on 3 November 2021*

I have replaced stock fans from my Unifi Ubiquiti USG Pro and I here the sound barely, before with stock fans I mom used to complain about noise while she was in other bedroom. Now no sound from the fans at all, for your reference I am not using any low noice adaptors. I will purchase two more to replace in 24 port PoE switch.

## Frequently Bought Together

- Noctua NF-A4x20 FLX, Premium Quiet Fan, 3-Pin (40x20mm, Brown)
- Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)

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*Product available on Desertcart Croatia*
*Store origin: HR*
*Last updated: 2026-07-21*