OWC Flex 1U4

4-Bay Thunderbolt™ Storage, Docking, and PCIE Expansion Rackmount Solution

OWC Flex 1U4



Drive Bays



Dock + 85W Charging1




Up to



X16 (X4) Lane


Expansion Slot






Drive Configurations



Ecosystem Options

Or Configure FLEX 1U4 Your Way

OWC Flex 1U4 front and back

The Rackmount Workflow Game-Changer

Since the launch of the OWC ThunderBay desktop storage line in 2014, computer users across the planet have continued to fall in love with it. They embrace its massively powerful RAID capacity and intense performance fueled by time-tested OWC reliability. Its appeal skyrocketed when it was infused with industry-first FLEXibility to create ThunderBay Flex 8.

Now businesses, institutions, studios, and creatives can go beyond the desktop with the OWC Flex 1U4. This innovative 4-bay rackmount solution is ready to fuel your endeavors with the best combination of storage capacity, Thunderbolt transfer performance, drive flexibility, and device expandability. With FLEX in its name, you can count on Flex 1U4 to be your rackmount workflow game-changer.

FLEXible Storage

Drive Diversity

Use SATA/SAS3 and U.2/M.24 NVMe drives for up to 128TB2 of capacity and real-world Thunderbolt speeds up to 2750MB/s

Drive Flexibility

Swap drives quickly and easily if/when needed

Get Maximum

Utilize U.2 NVMe SSDs as well as the OWC ecosystem of U.2 drives and adapters for incredible speed and flash density per bay

Powerfully Easy RAID

Create, manage, and monitor advanced RAID sets with OWC SoftRAID

Docking FLEXibility

  • Use It All

    Connect keyboards, mixers, cameras, displays, and mobile devices such as tablets with (2) USB-C 10Gb/s and (3) USB-A 10Gb/s ports.

  • Charge

    Keep your notebook powered with 85W via the upstream Thunderbolt port1

  • See More

    Connect up to an 8K display to the DisplayPort 1.45

FLEXpandable for Unique Needs

Do More

Add a half-length full-height single-width audio/video capture, 10Gb Ethernet, SSD storage, hardware RAID, or I/O card to the PCIe x16 lane (at x4 speed) slot

Shop PCIe Cards »


Daisy chain up to five devices or add an additional display with the second Thunderbolt (USB-C) port

Rack Up Workflow FLEXibility

You’ll turn your expandability and connectivity dreams into reality when you add Flex 1U4 to your rack or cart.

Add up to an 8K display via DisplayPort. And when you have a custom capture, recording, networking, or storage need, Flex 1U4 lets you install a PCIe card to conquer specialized tasks.

Connect mixers, keyboards, cameras, and other gear to your heart’s content as well as charge mobile devices with an ample variety of Thunderbolt and USB ports.

Use a mix of 2.5 or 3.5-inch SATA/SAS and U.2/M.2 NVMe drives with four quick-access, hot-swappable drive bays.

Future Ready

When your workflow needs change, the “FLEXpandability” of the OWC Flex 1U4 easily adapts. Add new drives, connect different devices, and install the PCIe expansion card of your choice – like the OWC 10G Ethernet PCIe Networking Card or the blistering fast OWC Accelsior 4M2 SSD for expanded performance storage capacity. By not locking you into an inflexible, single-task design, the OWC Flex 1U4 extends its useful life and maximizes your investment well into the future.

OWC Flex 1U4 with PCIe Card installed

OWC Accelsior 4M2 SSD PCIe card installation in the OWC Flex 1U4

Ideal for All Rackmount Environments

Flex 1U4 is like a bolt-in productivity supercharger for new or existing rack environments powered by a rack Mac Pro, MacBook Pro, or even a Mac mini. Whether you build your own custom drive and card configuration or select one of our convenient ready-to-run solutions, Flex 1U4 is ideal in a wide variety of settings:

School server room

In School

Perfect for taming ever-growing collections of digital files with easy integration and future drive capacity and performance scalability.

Workplace server room

At Work

Adds Thunderbolt speed and swappable drives to server closets, server rooms, or colocation center backup capabilities.

Backstage production crew

On Stage

Handles all the storage and peripheral connectivity needs “front of house” pros require for live performances.

DIT cart with OWC Flex 1U4

On Set

Easily fits into mobile DIT carts to capture multi-stream, hi-res footage at full framerate while daisy-chaining up to five additional Thunderbolt devices.

Music recording studio

In Studio

Expands storage and connectivity options of fixed racks.

Modern home theater

At Home

Great for installers creating a high-performance home entertainment server closet.

A Complete Swap and Share Ecosystem

When you need to move data outside or beyond the local network, Flex 1U4 helps you go with the flow. Thanks to the OWC U.2 ecosystem, moving and sharing data with Flex 1U4 is fast and easy. Swap out and ship a project from field to post in video production workflows. Move backup data to an offline colocation for backup workflows. The combination of Flex 1U4 and the OWC U.2 ecosystem opens a new dimension to data transfer possibilities.

OWC U.2 Ecosystem

Back row from left to right: OWC Thunderbay Flex 8, OWC Mercury Helios 3S, and OWC Mercury Pro U.2 Dual. Front row from left to right: OWC U.2 NVMe Interchange System and OWC U2 ShuttleOne (2).

OWC ThunderBay Flex 8

Take control of your media workflow with the world’s first 3-in-1 Thunderbolt storage, docking, and PCIe expansion desktop solution. Easily swaps U2 ShuttleOne and U2 Shuttles to/from the Flex 1U4.

Shop OWC ThunderBay Flex 8 »

OWC Helios 3S + U.2 NVMe Interchange System

Create an external Thunderbolt powered set to post U.2 solution that safeguards your data while lowering shipping costs.

Shop OWC Helios 3S »

OWC Mercury Pro U.2 Dual

Put blazing fast Thunderbolt powered storage and backup on a desktop with a compact two bay footprint that can use U2 ShuttleOne and U2 Shuttles.

Shop OWC Mercury Pro U.2 Dual »

OWC U2 Shuttle

Combine four NVMe M.2 SSDs into the world’s first 3.5-inch U.2 carrier shuttle to create a swappable, massive capacity RAID solution.

Shop OWC U2 Shuttle »

OWC U2 ShuttleOne

Convert an NVMe M.2 “blade” style SSD into a swappable 2.5-inch U.2 SSD with the peace of mind that your drive is protected by the full metal, heat dissipating adapter.

Shop OWC U2 ShuttleOne »

Learn More About U.2 Technology Benefits on the Rocket Yard Blog

The Most Powerful RAID Tool on the Planet.

SoftRAID is the world’s fastest and most flexible application to configure, maintain, and protect your RAID volumes on Mac and PC. OWC enclosures include 3 Years of SoftRAID Premium.

  • High-Performance RAID 0/1/4/5/1+0 (10) volumes
  • Predictive Health Monitoring proactively notifies of Volume and Disk issues well before failure — provided on your computer and remotely
  • 35+ Years of Experience of Pro Support to provide peace-of-mind with setup help, ongoing questions, or urgent disk issues
  • And many more unique features.
  • Learn more about SoftRAID

M1 Macs require macOS 11.3 or later. SoftRAID is licensed per computer. RAID 1+0 (10) coming soon to Windows.

iMac Pro with SoftRAID
Thunderbolt Logo

Thunderbolt Made Easy

We make it easy to choose the right gear. Our Thunderbolt Certified products offer the same performance and functionality whether they are Thunderbolt 3 or Thunderbolt 4. And if you’re rocking a beloved Thunderbolt 2 machine, we offer an adapter so you can plug into our universe of award-winning solutions. No hassles, no confusion. That’s the OWC Difference.

Apple Mac models with Thunderbolt 2/Thunderbolt ports can be connected using an Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter and a Thunderbolt 2 cable (available separately). This configuration provides data transfer at up to 20Gb/s but does not support notebook charging.

OWC Flex 1U4 rack hardware

Ready to Rack

Flex 1U4 comes complete with hardware for mounting into most racks and cabinets.

OWC Thunderbolt Cable

OWC Thunderbolt Cable Included

OWC Flex 1U4 comes with a certified 0.7M OWC Thunderbolt Cable. But if your workflow demands a different length to make the connection, OWC Thunderbolt (USB-C) Cables are the perfect choice.

Professional Grade

Certified for Demanding Use

We understand having confidence in gear reliability is paramount to creative professionals. That’s why OWC Flex 1U4 solutions go through a multi-step performance certification prior to shipping. This ensures they arrive operating properly and immediately ready for demanding use.

OWC ClingOn

Work with Ultimate Confidence

Active workspaces expose gear to unexpected bumps and shoves. OWC ClingOn custom cable stabilizers (available separately) screw into the OWC Dock or OWC Drive housing to reduce – if not completely eliminate – cable strain on Thunderbolt and USB-C connections so you can work with ultimate confidence even in the highest foot traffic environments.

OWC, Trusted by Pros & Enthusiasts the World Over

OWC, Trusted by Pros & Enthusiasts the World Over

We build our hardware to the highest standards of reliability and performance. Because 100% reliability is always the goal, we rigorously quality test and back our hardware with a 5 Year OWC Limited Warranty and award-winning customer support.

Learn More
  1. Thunderbolt 2/Thunderbolt compatibility requires a certified Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) adapter and a Thunderbolt 2 cable (available separately). This configuration provides data transfer at up to 20Gb/s but does not support notebook charging.
  2. Up to 128TB supported via 4 x OWC U2 Shuttles (16 x 8TB NVMe M.2 SSDs) available soon.
  3. SAS drives are supported with SAS drive controller card (available separately).
  4. Up to four U.2 drives are supported. M.2 drives are also supported with M.2 to U.2 adapter such as the OWC U2 Shuttle and OWC U2 ShuttleOne (available separately).
  5. Full DisplayPort 1.4 capabilities depends on host computer support of DisplayPort 1.4 specification through its Thunderbolt connection, host computer GPU capabilities, and connecting cable capabilities.
  6. 5 Year OWC Limited Warranty for Hard Drive and Solid-State Drive solutions. 1 year OWC Limited Warranty for Enclosure only.