---
product_id: 47568525
title: "NF-A4x20 FLX, High-Performance Quiet Fan 40mm"
brand: "noctua"
price: "₨12637"
currency: LKR
in_stock: true
reviews_count: 13
category: "Noctua"
url: https://www.desertcart.lk/products/47568525-nf-a4x20-flx-high-performance-quiet-fan-40mm
store_origin: LK
region: Sri Lanka
---

# >150,000 h MTTF reliability 5000 RPM max speed Ultra-quiet 14.9 dB(A) NF-A4x20 FLX, High-Performance Quiet Fan 40mm

**Brand:** noctua
**Price:** ₨12637
**Availability:** ✅ In Stock

## Summary

> 🌀 Quiet power that keeps your gear cool and your workspace zen.

## Quick Answers

- **What is this?** NF-A4x20 FLX, High-Performance Quiet Fan 40mm by noctua
- **How much does it cost?** ₨12637 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.lk](https://www.desertcart.lk/products/47568525-nf-a4x20-flx-high-performance-quiet-fan-40mm)

## 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:** Crafted from fibre-glass reinforced PBT and backed by a 6-year warranty, this fan guarantees long-term, dependable performance.
- • **Compact Powerhouse:** Slim 40x40x20mm size fits seamlessly into tight 1U spaces, ideal for professional-grade network gear and compact PCs.
- • **Award-Winning Design:** Flow Acceleration Channels and Acoustic Optimisation frame deliver superior cooling with minimal noise—engineered for the discerning tech pro.
- • **Precision Airflow Control:** Three-speed FLX settings (5000/4400/3700 RPM) let you dial in the perfect balance of cooling power and whisper-quiet operation.
- • **Vibration-Free Performance:** Includes anti-vibration mounts and OmniJoin adaptor set for smooth, silent operation and easy integration with proprietary headers.

## Overview

The Noctua NF-A4x20 FLX is a premium 40mm high-performance fan designed for ultra-quiet, efficient cooling in compact spaces. Featuring three adjustable speeds up to 5000 RPM, advanced aerodynamic design, and anti-vibration accessories, it’s perfect for professional network equipment and small form-factor PCs. With a noise level as low as 14.9 dB(A) and a remarkable >150,000 hours MTTF, it combines durability with whisper-quiet operation, backed by a 6-year warranty.

## Description

Buy Noctua NF-A4x20 FLX, High-Performance Quiet Fan 40mm | High Airflow, Low Noise, 20mm Thick, for PC and Electronics Cooling, 3 Speed Settings 5000/4400/3700rpm 3-Pin: Case Fans - desertcart.com ✓ FREE DELIVERY possible on eligible purchases

Review: Better and quieter - Works great, same airflow but much quieter as other brands. Comes with all the adapters to fit perfectly in any device. Highly recommend.
Review: A fan that lives up to Noctua’s reputation - I recently upgraded the case for my computer. The new case had much quieter fans than my old one. Happy as a peacock, I set about using it, only to be disturbed by a high pitched whine that quickly got on my nerves. A little investigation and I discovered that the stock 40mm fan that helped cool a component on my motherboard was the culprit. So I went looking for a replacement. Enter the Noctua fan. I was familiar with Noctua from research I’d done about CPU cooler fans a few years ago. Their reputation is very good. That inspired my purchase of this fan over other less expensive brands. I wasn’t disappointed. This fan is quiet. There is very little noise other than the sound of air moving through it. Even that is minimal. Obviously, that is exactly what I was looking for, so it fits the bill perfectly. I wanted a fan that wouldn't disturb the peace. This one is quiet as a mouse. Overview: The fan comes with a standard 3 pin connector that is common on many motherboards and electronics. It also has an assortment of additional items in the box. This includes a short extension cable, low noise adapters that reduce the speed of the fan and 4 omnijon clips , so you can easily remove the included 3 pin connector and connect a new one if needed. A set of case screws and anti-vibration mounts are also included in the box. The fan itself has silicon pads on the corners to help cut down on vibration. Unlike other reviewers, I had no issue with them falling off. I did not use any of the mounting options provided in the box as I simply used the mounting solution my mother board already provided. I suspect that the anti-vibration mounts would be one time use. They’re shaped like Christmas tree clips and would probably get shredded when removed. Another bonus is that it has a nicely presented set of instructions explaining how to use the adapters and silicon mounts. Bottom line: The packaging for this fan is crazy. It comes in a double book fold cardboard box with a molded plastic tray. I guess they’re trying to give the impression of quality with the packaging, but it really seems like overkill for a product that cost only 14 dollars. Noctua wants its customers to feel like they got a quality product by providing one and packaging it like one. Well, it worked. This is a great little fan.

## 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
- 3-pin FLX version provides 5000/4400/3700rpm speed settings via Low-Noise Adaptors to fine-tune the fan for maximum airflow or near-silent operation
- Includes anti-vibration mounts, fan screws, extension cable and OmniJoin adaptor set for connecting the fan to proprietary fan headers

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B072JK9GX6 |
| Air Flow Capacity | 9.4 cubic meter per hour |
| Best Sellers Rank | #102 in Computer Case Fans |
| Brand | Noctua |
| Brand Name | Noctua |
| Compatible Devices | Desktop |
| Cooling Method | Air |
| Customer Reviews | 4.8 out of 5 stars 2,525 Reviews |
| Included Components | 1 |
| Item Dimensions L x W x H | 1.57"L x 1.57"W x 0.79"H |
| Item Highlight | High Airflow, Low Noise, 20mm Thick, for PC and Electronics Cooling, 3 Speed Settings 5000/4400/3700rpm 3-Pin |
| Manufacturer | Noctua |
| Material Type | Fibre-glass reinforced PBT |
| Maximum Rotational Speed | 5000 rpm |
| Model | NF-A4x20 FLX |
| Noise Level | 14.9 db |
| Number of Packs | 1 |
| Part Number | NF-A4x20 FLX |
| Power Connector Type | 3-Pin |
| Product Dimensions | 1.57"L x 1.57"W x 0.79"H |
| UPC | 841500110116 |
| Unit Count | 1 Count |
| Voltage | 12 volts |
| Warranty Description | 6 year manufacturer’s warranty |

## Product Details

- **Air Flow Capacity:** 9.4 cubic meter per hour
- **Brand:** Noctua
- **Compatible Devices:** Desktop
- **Cooling Method:** Air
- **Material:** Fibre-glass reinforced PBT
- **Maximum Rotational Speed:** 5000 rpm
- **Noise Level:** 14.9 db
- **Power Connector Type:** 3-Pin
- **Product Dimensions:** 1.57"L x 1.57"W x 0.79"H
- **Voltage:** 12 volts

## Images

![NF-A4x20 FLX, High-Performance Quiet Fan 40mm - Image 1](https://m.media-amazon.com/images/I/71lyRpVR4OL.jpg)

## Available Options

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

## Questions & Answers

**Q: Whats the cfm of this fan?**
A: The output, converted from 9.4 m3/h is just 5.5 cfm, very low indeed.

**Q: 14.9dba at what speed?**
A: 5000rpm.

**Q: How many dB is this fan?**
A: 14.9db(a)

**Q: What is the mtbf. How many hours of life can I expect from one of these?**
A: Not sure about the Mtbf, but i purchased 2 of this in Jan 2020, and they have been running 24/7 till now with no problems. Installed them in my 2 poe+ switches

## Customer Reviews

### ⭐⭐⭐⭐⭐ Better and quieter
*by J***S on September 20, 2026*

Works great, same airflow but much quieter as other brands. Comes with all the adapters to fit perfectly in any device. Highly recommend.

### ⭐⭐⭐⭐⭐ A fan that lives up to Noctua’s reputation
*by L***N on January 12, 2019*

I recently upgraded the case for my computer. The new case had much quieter fans than my old one. Happy as a peacock, I set about using it, only to be disturbed by a high pitched whine that quickly got on my nerves. A little investigation and I discovered that the stock 40mm fan that helped cool a component on my motherboard was the culprit. So I went looking for a replacement. Enter the Noctua fan. I was familiar with Noctua from research I’d done about CPU cooler fans a few years ago. Their reputation is very good. That inspired my purchase of this fan over other less expensive brands. I wasn’t disappointed. This fan is quiet. There is very little noise other than the sound of air moving through it. Even that is minimal. Obviously, that is exactly what I was looking for, so it fits the bill perfectly. I wanted a fan that wouldn't disturb the peace. This one is quiet as a mouse. Overview: The fan comes with a standard 3 pin connector that is common on many motherboards and electronics. It also has an assortment of additional items in the box. This includes a short extension cable, low noise adapters that reduce the speed of the fan and 4 omnijon clips , so you can easily remove the included 3 pin connector and connect a new one if needed. A set of case screws and anti-vibration mounts are also included in the box. The fan itself has silicon pads on the corners to help cut down on vibration. Unlike other reviewers, I had no issue with them falling off. I did not use any of the mounting options provided in the box as I simply used the mounting solution my mother board already provided. I suspect that the anti-vibration mounts would be one time use. They’re shaped like Christmas tree clips and would probably get shredded when removed. Another bonus is that it has a nicely presented set of instructions explaining how to use the adapters and silicon mounts. Bottom line: The packaging for this fan is crazy. It comes in a double book fold cardboard box with a molded plastic tray. I guess they’re trying to give the impression of quality with the packaging, but it really seems like overkill for a product that cost only 14 dollars. Noctua wants its customers to feel like they got a quality product by providing one and packaging it like one. Well, it worked. This is a great little fan.

### ⭐⭐⭐⭐⭐ Quieted Down My Dock
*by R***Y on February 1, 2021*

A while back I had picked up one of those popular multi-drive docks for the SSDs in my desktop. It's a popular dock that will go nameless for this review. The worst thing about it, the reviews warned, was the fan. It wasn't bad at first but over time had gotten quite noisy - enough that I went searching for a replacement. I already use one of Noctua's CPU coolers and it's awesome so this NF-A4x20 FLX was kind of a no-brainer. It does no disappoint! The dock's quieter than ever. What's more, each drive in the dock runs about a degree cooler than before with no settings changes. Everyone knows that heat is the enemy so this is a small but measurable win. Now, the bad - at least for my particular application. None of the mounting screws supplied with the fan would fit. It's not Noctua's fault. The original fan was perhaps half the thickness of this one. The longer supplied screws were a bit too long - there's a circuit board about 4 millimeters behind the mounting holes in the doc, so screw length was critical. I ended up cutting screws from my parts bin to the exact length I needed. I really wish I could have used the rubber pull-through mounts Noctua included because they would have surely quieted things down even more. I think I could if I wasn't too lazy to tear apart the dock to customize the fan mount surface. Maybe for the future. So I've been using this fan now for a little better than a month and it's as quiet as ever. If you can manage the thickness, this is an awesome 40 millimeter square replacement fan.

## Frequently Bought Together

- Noctua NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM)
- Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)
- Noctua NF-A4x20 PWM, Premium Quiet Fan, 4-Pin (40x20mm, Brown)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.lk/products/47568525-nf-a4x20-flx-high-performance-quiet-fan-40mm](https://www.desertcart.lk/products/47568525-nf-a4x20-flx-high-performance-quiet-fan-40mm)

---

*Product available on Desertcart Sri Lanka*
*Store origin: LK*
*Last updated: 2026-10-19*