---
product_id: 1476697
title: "NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)"
brand: "noctua"
price: "239 kr"
currency: DKK
in_stock: true
reviews_count: 8
category: "Noctua"
url: https://www.desertcart.dk/products/1476697-nf-a4x10-flx-premium-quiet-fan-3-pin-40x10mm-brown
store_origin: DK
region: Denmark
---

# 4500/3700 RPM dual-speed control Ultra-quiet max 17.9 dB(A) noise level >150,000 h MTTF premium durability NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)

**Brand:** noctua
**Price:** 239 kr
**Availability:** ✅ In Stock

## Summary

> 🛡️ Silence Meets Power: The Ultimate Mini Fan Upgrade You Didn’t Know You Needed

## Quick Answers

- **What is this?** NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown) by noctua
- **How much does it cost?** 239 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/1476697-nf-a4x10-flx-premium-quiet-fan-3-pin-40x10mm-brown)

## 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:** Fiberglass-reinforced PBT material and >150,000 hours MTTF ensure long-term reliability and peace of mind.
- • **Compact Yet Mighty:** 40x40x10 mm size fits perfectly in tight spaces like 3D printers, DVRs, NAS, and network devices without compromising airflow.
- • **Precision Airflow Control:** Dual-speed FLX adapters let you fine-tune between powerful 4500 RPM airflow or ultra-quiet 3700 RPM mode.
- • **Whisper-Quiet Performance:** Engineered with advanced acoustic optimization for near-silent operation even at max speed.
- • **Universal Compatibility Kit:** Includes anti-vibration mounts, extension cables, and OmniJoin adaptors for seamless integration with diverse 12V 3-pin systems.

## Overview

The Noctua NF-A4x10 FLX is a premium 40x40x10 mm 12V 3-pin fan designed for ultra-quiet, high-performance cooling in compact devices. Featuring dual-speed control (4500/3700 RPM), advanced acoustic optimization, and a comprehensive accessory kit, it delivers superior airflow at a whisper-quiet 17.9 dB(A) noise level. Built with durable fiberglass-reinforced PBT and rated for over 150,000 hours MTTF, it’s the go-to upgrade for professionals seeking reliable, silent cooling in 3D printers, DVRs, NAS, and network equipment.

## Description

Buy Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown): Case Fans - desertcart.com ✓ FREE DELIVERY possible on eligible purchases

Review: Works Fantastic In Lorex Security Camera DVR - Wow! I had to write this review! Based on the other reviews, I purchased this product (thanks to all reviewers!). I saw that another reviewer commented on the accessories this came with...that the accessories allowed a person to tackle any project. I thought "Well, that's nice. But I'm sure I'll just be able to hook this up without the need." In part, I thought this because I saw the fans in my Lorex DVR connected with a TWO pin end, and the desertcart picture displays a TWO pin end. Well, I was wrong...the unit ships with a THREE pin connector as the "default". So, I too was super happy with the additional accessories or else I would have been stuck! Here's more... My Lorex DVR has two fans. The fans in the Lorex DVR are "Fonsoning fsy40s12m." This company is in China. An email to them went unresponded to. An online research revealed only ONE seller that would sell these in lots of 50 each at a minimum...I only needed two! The fans in my Lorex DVR were LOUD already, but, when one started to go (after only about a year and four months), it became unbearably loud! Lorex support is horrible, as is their warranty (one year). I was told to either send in the DVR for a charged repair or replace the entire DVR. After conducting a ton of research, I discovered that the Lorex fans are 40mm (each side length) and 10mm deep...I received quite the education as someone who started out with zero know-how on this. So, I opened up the fan packaging...the cable had THREE pins for the connector...not TWO like what I needed and what the desertcart picture displayed. Okay, well this came with a 3 to 2 pin connector adapter...I thought "no problem." By the way, there is also an extension cable, in the event your fan is placed far from the power supply...very nice. Back to the 3 to 2 pin adapter...I put it in and assembled the entire DVR...a LOT of work (at least for plain old me). After all that work, the fan didn't even budge! Ouch! Then, I saw these other adapters included by Noctua. The instructions stated that, where the polarity is OPPOSITE what the connectors are set up as, then these special adapters can be used (you may be wondering what the heck I'm talking about, but to explain that would be tough here. Perhaps an easy way to explain it is if the wires on the Noctua are opposite what the power supply is in your unit...meaning, the red wire needs to connect to the black wire instead of red, etc.). I thought..."Oh no. Do I need to do this???!!! I can't just use an adapter?" Yes...I did. But, better this than not having a working fan. Unfortunately, you don't know if you have a reversed polarity problem until the fan is plugged in, so I recommend NOT reassembling the entire unit until you've tested the fan first, if possible and if it's safe. So, I went back to the drawing board and took the old fans out and cut their wires close to where the fans are located....because, with this setup, you need to use the pins of the ORIGINAL fans. You then need to insert the ends of the ORIGINAL fans (i.e., the cords with the pins connected to them...not the cord with the original FAN connected to it) into these special adapters with the ends of the NOCTUA fans...no wire stripping is necessary. You just push the buttons down on these special adapters with a pair of pliers and...voila...you have a makeshift fan connection using the NOCTUA fans with the ORIGINAL fans pins. I plugged them in and I had motion!! Now, one of the accessories comes with a special cable that will reduce the RPM's of the fans to make them quieter. I thought, "Hmmmm...the 'normal' RPM's on these things must be a bit loud for Noctua to include such a cable." NO!! They are super quiet! They are quieter than the original fans when I first received the Lorex DVR brand new!!! In fact, had I known about these Noctuas back then, I might have just installed them at that time!!! I need to stand next to the DVR to hear the fans (maybe five to ten feet or so). Oh, I almost forgot...the connections of the fans themselves. So, the old Lorex fans were screwed into the case of the DVR. There was a special nut in the back of the Lorex fans to accept the screw used. The nut wouldn't fit the Noctua since the nut was hexagonal, and the back of the Noctua is round. "Now what am I going to do?" I thought! Well, Noctua included an answer for this too!!!! There are four included rubbery inserts that you put through the case holes for your unit. In this case, I only needed two per fan. I couldn't use four because there were only two holes in the DVR at the bottom. So, I inserted these rubber pieces through the two bottom holes and used only the two bottom holes on the fan. I found that my needle-nosed pliers were very handy here because I didn't have much space and I really wanted a snug fit, so I used the pliers to pull the rubber pieces through. In fact, these rubber pieces are supposed to decrease sound even more, in addition to the rubber bumpers on them. The fans are super secure, super quiet, super efficient, they have accessories that REALLY helped my scenario. I couldn't be happier! And, I didn't have to spend hundreds or thousands of dollars on a repair or replacement of my DVR and lose any more time without it. And, they are quieter than the original fans...without the RPM reduction cable! When I looked, these fans are about twice the price of another fan I saw on desertcart, but, in my opinion, WELL worth it. If you have a DVR with fans that are going bad or just plain noisy, these Noctuas just my be your ticket.
Review: Super quiet - Premium fan - Amazing fan. This thing is super quiet. I bought it to replace a 40mm fan in my 3D printer, and I couldn't even tell this thing was spinning when I powered it up the first time. I thought something was wrong, but it was working just fine. That's how quiet this is. With my old fan, the fan noise was the primary sound you heard when the 3D printer was running. This fan makes my stepper motors seem extra loud, but in reality I'm just taking the constant fan drone out of the picture. This fan does a lot with the aerodynamics of the blades and housing to maintain airflow, but also reduce noise. There are integrated noise isolation pads on the corners of the fan to avoid transmitting vibrations into whatever it's mounted to, further reducing the sound from this fan. I didn't use them for my application, but they even include silicone mounts to completely avoid any screws or hard contact with the frame when mounting the fan. This man has been engineered to be extremely quiet and still meet the performance expectations for air flow. The packaging reflects the premium level of quality of the fan. The accessories and connectors included pretty much make this compatible for any use out of the box. It's all pros for this fan. I don't have any cons other than in not a fan of the Noctua color scheme. This fan is worth it if you are looking for something silent with premium quality. This fan is worth the cost. In reality, yes they cost more than generic fans of this same size, but the cost difference is made up for in the silence and quality that this fan gives you. I would recommend this to anyone.

## Features

- Premium quiet fan, 40x40x10 mm, 12V, 3-pin Molex, 4500/3700 RPM, max. 17.9 dB(A), >150,000 h MTTF
- Award-winning 40x10mm A-series fan with Flow Acceleration Channels and Advanced Acoustic Optimisation frame for superior quiet cooling performance
- Ideal replacement for noisy or broken 12V 4cm fans in 3D printers, DVRs, NAS, switches, routers, other network and storage devices, etc.
- 3-pin 12V FLX version can be run 4500 or 3700 rpm using the supplied Low-Noise Adaptors to fine-tune the fan for maximum airflow or near-silent operation
- Includes anti-vibration mounts, fan screws, Low-Noise Adaptor, extension cable and OmniJoin adaptor set for connecting the fan to proprietary fan headers

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B009NQLT0M |
| Air Flow Capacity | 60.1 Cubic Meters Per Hour |
| Best Sellers Rank | #46 in Computer Case Fans |
| Brand | Noctua |
| Brand Name | Noctua |
| Compatible Devices | Desktop |
| Cooling Method | Air |
| Customer Reviews | 4.8 out of 5 stars 11,118 Reviews |
| Global Trade Identification Number | 04716123314691, 07123290462549, 07133363436841 |
| Item Dimensions L x W x H | 1.57"L x 0.39"W x 1.57"H |
| Item Height | 10 millimeters |
| Item Weight | 50 Grams |
| Manufacturer | Noctua |
| Material Type | Fibre-glass reinforced PBT |
| Maximum Rotational Speed | 4500 RPM |
| Noise Level | 17.9 Decibels |
| Power Connector Type | 3-Pin |
| Product Dimensions | 1.57"L x 0.39"W x 1.57"H |
| UPC | 163121136772 809185325669 806291857176 804066543873 842431014054 102930672934 782386476753 172302657890 132017920719 808111662861 809385174852 168141421648 851905102548 |
| Unit Count | 1.0 Count |
| Voltage | 12 Volts |
| Warranty Description | 6 year manufacturer’s warranty |

## Product Details

- **Air Flow Capacity:** 60.1 Cubic Meters Per Hour
- **Brand:** Noctua
- **Compatible Devices:** Desktop
- **Cooling Method:** Air
- **Material:** Fibre-glass reinforced PBT
- **Maximum Rotational Speed:** 4500 RPM
- **Noise Level:** 17.9 Decibels
- **Power Connector Type:** 3-Pin
- **Product Dimensions:** 1.57"L x 0.39"W x 1.57"H
- **Voltage:** 12 Volts

## Images

![NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown) - Image 1](https://m.media-amazon.com/images/I/81ud+v9ghlL.jpg)

## Questions & Answers

**Q: what is the CFM for this fan?**
A: 5

**Q: This might be a dumb question, but what is the operating voltage?  Don't see a rating anywhere in the description or reviews and hoping it's 12VDC.**
A: 12 volts DC. 3 pin connector but comes with a 2 pin adapter and extension cables.

**Q: Have anyone used this to replace the 35 mm assist fans on an asus sabertooth z87?**
A: I have it in my Asus Sabertooth Z170 S and it fits just fine! (just remove the two Anti-Vibration Pads in contact with the TUF Armor to be able to close the lid).
Take into consideration that in my version of the Sabertooth, the assistant fan position is vertical, inside the TUF Thermal Armor, between the IO Shield and the heatsink VRM, and works as an intake fan, to blow fresh air into the motherboard. 
Every Sabertooth Assistant Fans are designed to work differently. I believe in your motherboard the fan is place horizontally, on Top of the TUF Thermal Armor. 
Also the fans needed for your Sabertooth Z87 had a mini 3 pin connector, my motherboard use 3 or 4 pin (regular size) connectors. Therefore the original assistant fan of the Sabertooth Z87 cannot be plugged in the Assist Fan 1 connector of my Sabertooth Z170 S. I know this because I was looking for the fans for my motherboard and buy the Z87 version by mistake, couldn't use it, so I buy the 40mm Noctua, and it works great! Really improved the temperature inside my case. Also my motherboard use 40mm fans. I'm not sure of the Z87 assistant fans size, but putting the two of them together, are exactly the same size, only thing adding up to the size variation, are the Noctuas silicone anti vibrations pads, that can be removed.
Hope this helps even a little bit.

**Q: What is the sound decible rating**
A: http://noctua.at/en/products/fan/nf-a4x10-flx/specification

17.9

## Customer Reviews

### ⭐⭐⭐⭐⭐ Works Fantastic In Lorex Security Camera DVR
*by J***E on December 11, 2013*

Wow! I had to write this review! Based on the other reviews, I purchased this product (thanks to all reviewers!). I saw that another reviewer commented on the accessories this came with...that the accessories allowed a person to tackle any project. I thought "Well, that's nice. But I'm sure I'll just be able to hook this up without the need." In part, I thought this because I saw the fans in my Lorex DVR connected with a TWO pin end, and the Amazon picture displays a TWO pin end. Well, I was wrong...the unit ships with a THREE pin connector as the "default". So, I too was super happy with the additional accessories or else I would have been stuck! Here's more... My Lorex DVR has two fans. The fans in the Lorex DVR are "Fonsoning fsy40s12m." This company is in China. An email to them went unresponded to. An online research revealed only ONE seller that would sell these in lots of 50 each at a minimum...I only needed two! The fans in my Lorex DVR were LOUD already, but, when one started to go (after only about a year and four months), it became unbearably loud! Lorex support is horrible, as is their warranty (one year). I was told to either send in the DVR for a charged repair or replace the entire DVR. After conducting a ton of research, I discovered that the Lorex fans are 40mm (each side length) and 10mm deep...I received quite the education as someone who started out with zero know-how on this. So, I opened up the fan packaging...the cable had THREE pins for the connector...not TWO like what I needed and what the Amazon picture displayed. Okay, well this came with a 3 to 2 pin connector adapter...I thought "no problem." By the way, there is also an extension cable, in the event your fan is placed far from the power supply...very nice. Back to the 3 to 2 pin adapter...I put it in and assembled the entire DVR...a LOT of work (at least for plain old me). After all that work, the fan didn't even budge! Ouch! Then, I saw these other adapters included by Noctua. The instructions stated that, where the polarity is OPPOSITE what the connectors are set up as, then these special adapters can be used (you may be wondering what the heck I'm talking about, but to explain that would be tough here. Perhaps an easy way to explain it is if the wires on the Noctua are opposite what the power supply is in your unit...meaning, the red wire needs to connect to the black wire instead of red, etc.). I thought..."Oh no. Do I need to do this???!!! I can't just use an adapter?" Yes...I did. But, better this than not having a working fan. Unfortunately, you don't know if you have a reversed polarity problem until the fan is plugged in, so I recommend NOT reassembling the entire unit until you've tested the fan first, if possible and if it's safe. So, I went back to the drawing board and took the old fans out and cut their wires close to where the fans are located....because, with this setup, you need to use the pins of the ORIGINAL fans. You then need to insert the ends of the ORIGINAL fans (i.e., the cords with the pins connected to them...not the cord with the original FAN connected to it) into these special adapters with the ends of the NOCTUA fans...no wire stripping is necessary. You just push the buttons down on these special adapters with a pair of pliers and...voila...you have a makeshift fan connection using the NOCTUA fans with the ORIGINAL fans pins. I plugged them in and I had motion!! Now, one of the accessories comes with a special cable that will reduce the RPM's of the fans to make them quieter. I thought, "Hmmmm...the 'normal' RPM's on these things must be a bit loud for Noctua to include such a cable." NO!! They are super quiet! They are quieter than the original fans when I first received the Lorex DVR brand new!!! In fact, had I known about these Noctuas back then, I might have just installed them at that time!!! I need to stand next to the DVR to hear the fans (maybe five to ten feet or so). Oh, I almost forgot...the connections of the fans themselves. So, the old Lorex fans were screwed into the case of the DVR. There was a special nut in the back of the Lorex fans to accept the screw used. The nut wouldn't fit the Noctua since the nut was hexagonal, and the back of the Noctua is round. "Now what am I going to do?" I thought! Well, Noctua included an answer for this too!!!! There are four included rubbery inserts that you put through the case holes for your unit. In this case, I only needed two per fan. I couldn't use four because there were only two holes in the DVR at the bottom. So, I inserted these rubber pieces through the two bottom holes and used only the two bottom holes on the fan. I found that my needle-nosed pliers were very handy here because I didn't have much space and I really wanted a snug fit, so I used the pliers to pull the rubber pieces through. In fact, these rubber pieces are supposed to decrease sound even more, in addition to the rubber bumpers on them. The fans are super secure, super quiet, super efficient, they have accessories that REALLY helped my scenario. I couldn't be happier! And, I didn't have to spend hundreds or thousands of dollars on a repair or replacement of my DVR and lose any more time without it. And, they are quieter than the original fans...without the RPM reduction cable! When I looked, these fans are about twice the price of another fan I saw on Amazon, but, in my opinion, WELL worth it. If you have a DVR with fans that are going bad or just plain noisy, these Noctuas just my be your ticket.

### ⭐⭐⭐⭐⭐ Super quiet - Premium fan
*by M***Y on December 26, 2018*

Amazing fan. This thing is super quiet. I bought it to replace a 40mm fan in my 3D printer, and I couldn't even tell this thing was spinning when I powered it up the first time. I thought something was wrong, but it was working just fine. That's how quiet this is. With my old fan, the fan noise was the primary sound you heard when the 3D printer was running. This fan makes my stepper motors seem extra loud, but in reality I'm just taking the constant fan drone out of the picture. This fan does a lot with the aerodynamics of the blades and housing to maintain airflow, but also reduce noise. There are integrated noise isolation pads on the corners of the fan to avoid transmitting vibrations into whatever it's mounted to, further reducing the sound from this fan. I didn't use them for my application, but they even include silicone mounts to completely avoid any screws or hard contact with the frame when mounting the fan. This man has been engineered to be extremely quiet and still meet the performance expectations for air flow. The packaging reflects the premium level of quality of the fan. The accessories and connectors included pretty much make this compatible for any use out of the box. It's all pros for this fan. I don't have any cons other than in not a fan of the Noctua color scheme. This fan is worth it if you are looking for something silent with premium quality. This fan is worth the cost. In reality, yes they cost more than generic fans of this same size, but the cost difference is made up for in the silence and quality that this fan gives you. I would recommend this to anyone.

### ⭐⭐⭐⭐⭐ Silent Upgrade for My NVR
*by D***. on November 22, 2025*

This fan is amazing. I put it in my Reolink RLN8-410 NVR, and it's extremely quiet and efficient. If you need a quality 40mm fan, this is the one to get, totally worth the price.

## Frequently Bought Together

- Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)
- Noctua NF-A6x25 FLX, Premium Quiet Fan, 3-Pin (60mm, Brown)
- Noctua NF-A4x20 FLX Computer Case Fan - Cooling Components (Computer Case, Fan, 4 cm, 3700 RPM, 5000 RPM, 4400 RPM)

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*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-01-29*