Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 12 - Jul 17
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Noctua NF-A4X20 5V PWM 40x20mm Premium Cooling FanFeaturing advanced aerodynamic design measures such as Flow Acceleration Channels and an AAO frame, the NF A4x20 5V PWM is a PWM enabled 5V variant of Noctuas highly optimised, premium quality quiet 40x20mm fan. The custom designed NE FD3 PWM IC that integrates Smooth Commutation Drive technology and Noctuas reference class SSO2 bearings guarantee superb running smoothness and excellent long term stability. Topped off with modular cabling, the
Featuring advanced aerodynamic design measures such as Flow Acceleration Channels and an AAO frame, the NF-A4x20 5V PWM is a PWM enabled 5V variant of Noctua’s highly optimised, premium quality quiet 40x20mm fan. The custom designed NE-FD3 PWM IC that integrates Smooth Commutation Drive technology and Noctua’s reference class SSO2 bearings guarantee superb running smoothness and excellent long-term stability. Topped off with modular cabling, the OmniJoin™ Adaptor Set and 6 years manufacturer’s warranty, the NF-A4x20 5V PWM is a premium choice for demanding 5V applications that require PWM control.
Being a 5V fan, the NF-A4x20 5V PWM cannot be run at 12V and will be damaged when used with typical 12V power sources such as PC motherboard fan headers
40x20mm size
Compared to Noctua’s award-winning NF-A4x10, the NF-A4x20 is twice as thick, which allows for increased static pressure performance and makes the NF-A4x20 ideal for demanding applications with high flow resistance.
5V PWM version
Many devices such as network or storage solutions use 5 volt 40mm fans with PWM speed control. With the same operating voltage, PWM support and the included OmniJoin™ adaptor set that makes it compatible with proprietary fan headers, the NF-A4x20 5V PWM is ideal for replacing noisy or broken 5V 40mm fans with PWM.
Polarity protection
As many devices using 5V fans feature proprietary connectors, and documentation of the pin alignment may not be available, the fan features an integrated diode for polarity protection. This way, you're on the safe side if you accidentally connect it with reverse polarity.
Flow Acceleration Channels
The NF-A4x20 impeller features suction side Flow Acceleration Channels. By speeding up the airflow at the crucial outer blade regions, this measure reduces suction side flow separation and thus leads to better efficiency and lower vortex noise.
AAO frame
Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency.
Stepped Inlet Design
Noctua's Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment and increases suction capacity, especially in space-restricted environments.
Inner Surface Microstructures
With the tips of the fan blades ploughing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed, which results in reduced blade passing noise and improved airflow and pressure efficiency.
Integrated Anti-Vibration Pads
Integrated Anti-Vibration Pads made from extra-soft silicone minimise the transmission of minute vibrations while maintaining full compatibility with all standard mounting systems and fan clips used on heatsinks.
Custom-designed PWM IC with SCD
Supporting fully automatic PWM speed control, the fan uses Noctua's custom-designed NE-FD3 5V PWM IC that integrates Smooth Commutation Drive (SCD) technology. By providing smoother torque impulses, SCD suppresses PWM switching noises and thus makes the fan quieter at low speeds.
OmniJoin™ adaptor set
Many devices featuring 40mm fans use proprietary fan headers, so the NF-A4x20 comes with Noctua's OmniJoin™ adaptor set. Just cut the original fan's cable, fix it to the adaptor using the supplied 3M Scotchlok™ connectors and you can plug the NF-A4x20 to proprietary fan headers!
Extensive cabling options
The fan's short 20cm primary cable minimises cable clutter in typical applications while the supplied 30cm extension provides extended reach when necessary. Both cables are fully sleeved and a 4-pin y-cable allows the connection of a second fan to the same PWM fan header for automatic control.
SSO2 bearing
The NF-A4x20 features the further optimised second generation of Noctua's renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision and durability.
6-year manufacturer’s warranty
Noctua fans are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the NF-A4x20 features an MTTF of more than 150.000 hours rating and comes with a full 6-year manufacturer’s warranty.
Technical Specifications
Size: 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
Min. rotational speed (PWM, +/-20%): 1100 RPM
Airflow: 9,4 m³/h
Acoustical noise: 14,9 dB(A)
Static pressure: 2,26 mm H₂O
Max. input power: 0,5 W
Max. input current: 0,1 A
Operating voltage: 5 V
Voltage: PWM signal 5 V
MTTF: > 150.000 h
Warranty: 6 years
Package includes:
- Noctua NF-A4X20 5V PWM Cooling Fan
- 4-pin y-cable
- 30cm extension cable
- OmniJoin™ adaptor set
- NA-AV3 anti-vibration mounts
- Fan screws
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.8 ★★★★★
Based on 2354 reviews
Sort
Product Reviews
★★★★★ 5
A wonderfully combo of prophetic word, scripture and history
Format: Paperback
A wonderful combo of the prophetic, scripture and history. Amanda Grace puts the truth into this book. Many little but important facts, truths and meanings to words names places etc to expand ones knowledge of who God is and how we all can get personal with Him. I also love and appreciate the reminders and again the truths of how history repeats itself and how now in 2025 we as Gods ppl need to step up once again and perhaps the last time before the door closes. Religion is man made, the Word is not and this book, well written and easy to take to heart will help anyone looking for truth and help in discerning satans twisted lies from Gods truth The Word. Blessings to all who read...
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 12, 2025
★★★★★ 5
Truthful
Format: Paperback
Awesome read!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 13, 2026
★★★★★ 5
With 76 pants in a pack, I find them to be an excellent value for the price
Size: 2T-3T, Unit Count: 76
As a parent navigating the potty training journey, I can confidently say that Pull-Ups Boys' Skin Essentials Potty Training Pants have been a game changer for both my child and me. Here’s why I love them and what makes them an essential part of our potty training routine.
Comfort and Fit:
One of the standout features of these training pants is their soft and gentle fabric. The Skin Essentials line is designed to be hypoallergenic and includes ingredients like aloe to help soothe and protect my little one’s sensitive skin. The fit is great for my toddler, providing just the right amount of stretch and comfort, which is crucial during this transitional phase. My child can move freely, whether he’s playing, jumping, or running around.
Absorbent and Reliable:
The absorbency of these training pants is impressive. They hold up well during the day and help manage any accidents without causing a mess. I appreciate that they have a wetness indicator, which makes it easy to know when it's time for a change, helping to instill good habits as we continue potty training.
Easy to Use:
Pull-Ups are designed for independence, which is perfect for toddlers eager to take control of their potty training. They pull up and down like regular underwear, allowing my child to practice pulling them on and off, which builds confidence. Plus, the easy-open sides are a lifesaver for quick changes when we’re on the go.
Fun Designs:
Kids love fun and engaging designs, and these training pants deliver! The playful graphics featuring beloved characters make my son excited to wear them. This little touch has made a big difference in how he approaches potty training—he’s proud to wear them and feels like a “big boy.”
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 8, 2024
★★★★★ 5
Very soft, high quality pull ups, but quite expensive
Size: 3T-4T, Unit Count: 112
We really enjoy this brand of pull ups as they are the softest of all the pull ups and they have adjustable straps on each side of the pull up. Most brands just are pull ups with no bells and whistles, but these have Velcro straps on each side that allow you to adjust the size but more importantly for us, it allows us to change his pull up without having to take the pants fully off. This is really convenient when we’re in a hurry or out for the day. The absorbency is some of the best diapers I’ve ever used. I feel I’m a diaper connoisseur and have tried everything from expensive to cheaper generic brands and we continue to buy these because of the quality, the Velcro straps, and also because of the reduction in substances included in the product, which is quite important for us as my sons skin gets irritated easily. The one thing that’s a negative is that they are very expensive. Diapers in general are crazy expensive but these are more expensive than other brands. I usually buy these in bulk on Sam’s website but saw they were on sale and had a deal where you subscribe and get 25% off so I bought two big packs of 112 diapers and ended up spending around $82 for 224 diapers, which is a pretty good deal. I do wish they would sell these for cheaper and unfortunately don’t think I’ll be buying them from Amazon unless they have deals such as I described above. I do overall recommend them though as they are better than any other pull up brand we’ve ever used.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 22, 2024
★★★★★ 5
Gentle on skin, strong on progress
Size: 4T-5T, Unit Count: 60
These Pull-Ups are a win for both toddlers and tired parents. The Skin Essentials design feels ultra-soft and breathable—ideal for sensitive skin and long wear. I love that they’re dermatologist-approved and sized just right for 38–50 lbs, which adds comfort and confidence during potty training.
The cute prints add kid-friendly flair, and the sides are stretchy but easy for little hands to pull down themselves—big bonus for growing independence. With 60 pants per box, it’s a solid value for families going through this milestone, even with the slightly higher price tag.
At $39.09 and backed by Amazon’s Choice status and 4.7 stars across 600+ reviews, they’ve earned their spot in our routine. Bonus: over 1,000 purchases last month show we’re not the only ones loving them.
If you’re potty training and want gentle, effective help for sensitive skin, these Pull-Ups check all the boxes.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 27, 2025