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- USA
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Ships within 48 hours · Estimated delivery Jul 5 - Jul 10
For Your Every Summer RSVP, with Code: SUMMER15
Description
Synology Network Attached Storage FX2421 24 bay expansion FlashExpansion FX2421 (Diskless) RetailMPN FX2421 Applied Models Supports creating volumes across different units FS series: FS6400, FS3600, FS3400 Notes Expansion Unit FX2421 can only be used with identical expansion units. DSM version requirement: 6. 2. 3 25426 2 or later version. To have better performance, we recommend creating storage volumes physically located within the same NAS or Expansion Unit, rather than creating volumes across your NAS and Expansion Unit. Storage Drive Bays 24
MPNFX2421
Applied Models
Supports creating volumes across different units
FS series:FS6400, FS3600, FS3400
Notes
Expansion Unit FX2421 can only be used with identical expansion units.
DSM version requirement: 6.2.3-25426-2 or later version.
To have better performance, we recommend creating storage volumes physically located within the same NAS or Expansion Unit, rather than creating volumes across your NAS and Expansion Unit.
Storage
Drive Bays
24
Compatible Drive Type
2.5" SAS HDD
2.5" SAS SSD
2.5" SATA SSD
Maximum Internal Raw Capacity
92.16 TB (3.84 TB drive x 24) (Capacity may vary by RAID types)
Hot Swappable Drive
Yes
RAID Management through Synology DSM
Yes
Notes
"Compatible drive type" indicates drives that have been tested to be compatible with Synology products. This term does not indicate the maximum connection speed of each drive bay.
External Ports
SAS IN-port
1
SAS OUT-port
1
Appearance
Rack Installation Support
4-post 19" rack (Synology Rail Kit - RKS1317)
Notes
The rail kit is sold separately
Power
Power Supply Unit / Adapter
500 W
AC Input Power Voltage
100 V to 240 V AC
Power Frequency
50/60 Hz, Single Phase
Power Consumption
190.99 W (Access)
British Thermal Unit
651.68 BTU/hr (Access)
Redundant Power Supply (for RP model)
Yes
Notes
Power consumption is measured when it is fully loaded with HGST 1.8TB HUC101818CS4204 hard drive(s).
Temperature
Operating Temperature
0oC to 35oC (32oF to 95oF)
Storage Temperature
-20oC to 60oC (-5oF to 140oF)
Relative Humidity
5% to 95% RH
Others
System Fan
80 mm x 80 mm x 4 pcs
Easy Replacement System Fan
Yes
Noise Level
57 dB(A)
Notes
Noise Level Testing Environment: Fully loaded with Toshiba 600GB AL14SEB060N hard drive(s) in the idle state. Two G.R.A.S. Type 40AE microphones, each set up 1 meter away from the Synology NAS at the front and rear. Background noise: 16.49-17.51 dB(A), Temperature: 24.25-25.75oC, Humidity: 58.2-61.8%
Certification
UL
Environment and Packaging
Environment
RoHS Compliant
Packaging Content
Main Unit X 1
Accessory Pack X 1
AC Power Cord X 2
Expansion Cable: MiniSAS-HD X 1
Quick Installation Guide X 1
Optional Accessories
2.5" SATA SSD: SAT5200
Rail Kit Sliding: RKS1317
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
4.7 ★★★★★
Based on 474 reviews
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Product Reviews
★★★★★ 5
Rowenta steam iron
Ya mi planca me esta dondo problem enpeso a liquiar agua desde ayer. Pork este productos no tienes una duracion mas larga?. Nesecito canvio por fabol gracias
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Reviewed in the United States on April 30, 2026
★★★★★ 5
Fast and easy refund.
I purchased an air fryer and got a 3 year warranty on it from Asirion. The air fryer stopped working and I was expecting the warranty process to be complicated and didn’t have high hopes for getting a replacement. I was surprised though, not only was the website easy to navigate and user friendly, they responded immediately. I got a printable return postage receipt, dropped off the air fryer at a UPS store, and within a couple of days got a full refund in my Amazon account. Great fast service.
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Reviewed in the United States on January 25, 2025
★★★★★ 5
Efficient
Fast and efficient, taking care of my claim
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Reviewed in the United States on February 26, 2026
★★★★★ 1
Be careful purchasing this.
We bought this for an ice-cream maker - they never sent the initial startup you bought this email. So I had to fight with them that yeah we bought it.
Then they classified it as an ice-maker - important for pictures later . Then we had bought the machine and insurance partially with gift cards not a big deal, right? - well, the machine cost $300ish but showed on the receipt total as $180ish - guess which amount they wanted to pay out for? Then they wanted pictures showing serial number and such on the machine. I sent them pictures of each side clearly showing no stickers. Take more pictures of the front and top because what you took wasn't good - MAYBE because you thought it was an ice-maker... Take a picture showing what doesn't work - it will spin and move, but the compressor broke so it won't get cold - NOT GETTING COLD is something I can't show... it was fun being told to take a video showing it not getting cold only to tell them yeah no I am not wasting my time doing that.
There was a lot of repetitive stuff but they did eventually pay out the correct amount. Would I buy it again? Yes. Is it as easy as they make it out to be? No.
Did I WANT to give this review? No, because I didn't want to leave a negative review. I am a very charming, nice, and personable guy that didn't want to be mean. Keep pestering me enough about leave a review about how great we are and you will get the review you probably did not want.
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Reviewed in the United States on November 17, 2023
★★★★★ 5
You can trust ASURION warranties!
ASURION was fantastic as always. Purchased a Nespresso machine for my DIL which she absolutely loved and two months before warranty expired it started leaking which broke her heart. ASURION stood behind their warranty and refunded purchase price which I transferred to my DIL so she could purchase another machine. That’s why I never hesitate to buy their warranty’s and why I love shopping Amazon! Both companies represent their clients well. Thanks to both!
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Reviewed in the United States on November 7, 2025