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Seagate

Seagate Expansion Portable, 4TB, External Hard Drive, 2.5 Inch, USB 3.0, for Mac and PC (STKM4000400)

  • Based on 7,656 reviews
Condition: New
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FREE refund/replacement until Jan 31, 2026

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Availability: Only 1 left in stock, order soon!
Fulfilled by LWC Store
Arrives Sunday, Mar 22
Order within 12 hours and 10 minutes
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Capacity: 4TB


Features

  • Sleek and simple portable drive design for taking photos, movies, music, and more on-the-go
  • Drag-and-drop file saving
  • USB 3.0 powered
  • Automatic recognition of Windows and Mac computers for simple setup (Reformatting required for use with Time Machine)
  • Enjoy peace of mind with the included limited warranty and Rescue Data Recovery Services
  • The available storage capacity may vary.

Description

Expansion portable drive is an easy-to-use solution for instantly adding storage to Windows or Mac—and taking those files on the go. Take advantage of fast data transfer speeds with USB 3.0 and consolidate files into a single location. Free up space on your computer with a simple drag and drop—file saving is that easy.

Digital Storage Capacity: 4000 GB


Hard Disk Interface: USB 3.0


Connectivity Technology: USB


Brand: Seagate


Special Feature: Portable


Hard Disk Form Factor: 3.5 Inches


Hard Disk Description: Mechanical Hard Disk


Compatible Devices: Desktop


Installation Type: External Hard Drive


Color: Black


Processor: ‎none


Hard Drive: ‎4 TB Mechanical Hard Disk


Card Description: ‎Dedicated


Brand: ‎Seagate


Series: ‎Seagate Expansion


Item model number: ‎STKM4000400


Hardware Platform: ‎Mac, PC


Operating System: ‎Windows


Item Weight: ‎6.4 ounces


Product Dimensions: ‎3.15 x 0.59 x 4.61 inches


Item Dimensions LxWxH: ‎3.15 x 0.59 x 4.61 inches


Color: ‎Black


Computer Memory Type: ‎DIMM


Flash Memory Size: ‎4 TB


Hard Drive Interface: ‎USB 3.0


Voltage: ‎28 Volts


Batteries: ‎1 Lithium Ion batteries required.


Manufacturer: ‎Seagate


Language: ‎English


Is Discontinued By Manufacturer: ‎No


Date First Available: ‎April 29, 2021


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Mar 22

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Reliable good storage
Capacity: 1TB
...just what I hoped for... I use this as a backup storage for my laptop. I teach a scripture class online for my church, and I have several power points. I'm able to store weekly PowerPoints with no issues. I have plenty of room to add many many more. I had no issues with the files transferring to the portable hard drive. ... show more
Reviewed in the United States on September 29, 2025 by Arah P.
    • Reliable and Easy to Use
Capacity: 1TB
Overall, a good choice for extra storage at a reasonable price.
Reviewed in the United States on March 3, 2025 by Gary
    • High quality great price
Capacity: 4TB
Really great. Have 1 for a few yrs now and got another for my son. Works fast and great price
Reviewed in the United States on March 11, 2025 by Bag was missing the top strap that you would use to hold with just your hand and the clip on the long strap was broken. You are definitely not getting what you see in the picture.
    • A Good Drive
Capacity: 5TB
So far this drive is working well - just plug it in and it works. Maybe not as fast as a SDD drive but it does the job at a reasonable cost.
Reviewed in the United States on October 30, 2022 by Richard Lundin
    • Storing for memories
Capacity: 4TB
This was such a great purchase for me. As my phone memory is limited. Having kids , it’s very important for my to capture every moment. And it’s not fun when you’re out of memory. I decided to buy this to store photos and clips of our family. A memory that we can look back on years later. This is very easy to use. You just have to connect it to your phone and computer and start copying/moving the files that you like. It’s very handy too and doesn’t take so much space of your bag whenever you want to take it whith you when traveling. ... show more
Reviewed in the United States on November 2, 2024 by Ana Rose Alwine
    • Great price and fits a ton of files
Capacity: 1TB
Review Image by Nichole Aguilera Nichole Aguilera
I have a small dtf transfer company that requires saving thousands of digital files. This does the trick!! I can’t rely on my laptop to save them all and it’s always best to have back up. I can now transfer them from one printer to the next and it has also saved hundreds of photos from my phone to help clear up storage ... show more
Reviewed in the United States on November 16, 2024 by Nichole Aguilera Nichole Aguilera
    • After several months of abuse, still works well
Capacity: 4TB
Works as expected Price seems very fair.
Reviewed in the United States on April 10, 2025 by wounded by sharp tools
    • Never disappointed.
Capacity: 5TB
I've used these for years for photo back up. They can sit for years and rev up just fine. Capacity is just what I need. Windows 11. Transfer rate doesn't matter. I've got time and I can walk away.
Reviewed in the United States on December 28, 2023 by Stephen A. Levine

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