Name: OWC Express 4M2 Four-Slot USB4 (40Gb/s) External Storage Enclosure *open/complete*
Brand: OWC
SKU: OWCUS4EXP4M2O
Price: 218.75 USD
Availability: InStock

The Best DIY RAID You Wanted

We heard you loud and clear (pun intended) when you said you loved everything about the Express 4M2 but wanted it quieter. After adding smart adaptive fans that only turn on when needed for near silent operation, we decided to give it USB4 connectivity for the optimum blend of compatibility, performance, and affordability. Now you can build a desktop/shuttle high-performance RAID with your choice of NVMe M.2 SSDs and get up to 3200MB/s performance with USB4, Thunderbolt, and USB-C Macs and PCs.

Maximum Speed from Your Machine

The Express 4M2 is the fastest multiple NVMe SSD enclosure we offer and was purposefully built so you can utilize the maximum performance capability of your Mac or PC with full compatibility:

Express 4M2 Connected To...	Runs As	Up to Real-World Speed
Mac computers with Apple silicon M1/M2/M3/M4/M5	USB4 (40Gb/s)	3200MB/s
USB4 (40Gb/s) port on any PC	USB4 (40Gb/s)	3200MB/s
Thunderbolt 5 port on any Mac or PC	USB4 (40Gb/s)	3200MB/s
Thunderbolt 4 port on any Mac or PC	USB4 (40Gb/s)	3200MB/s
Thunderbolt 3 port on Intel Mac	Thunderbolt (40Gb/s)	3000MB/s
Thunderbolt 3 port on PC	USB 3.2 (10Gb/s)	990MB/s
USB 3.2 port on PC	USB 3.2 (10Gb/s)	990MB/s

Highly Capable

Up to 3200MB/s real-world performance ^{1, 2}

Highly Compatible

Use with USB4, Thunderbolt, and USB-C Macs and PCs

Highly Reliable

Aircraft grade aluminum offers rugged protection of installed SSDs plus effective heat dissipation to keep everything cool for consistent top speed

Near Silent Operation

Engineered with smart, adaptive fans that activate only when needed or under heavy load, making it ideal for uninterrupted creative focus

DIY Easy

Use your choice of NVMe M.2 2230, 2242, or 2280 SSDs

Built for RAID

Just add your own RAID management software, like OWC SoftRAID; the fastest and most flexible RAID 0/1/4/5/1+0 (10) tool. Also supports Apple Disk Utility RAID, Windows Disk Management RAID, and Windows Storage Spaces

Complete

Includes USB-C 40Gb/s cable

Stable

Included stand ensures maximum desktop placement stability

Front and back view of the Express 4M2 with USB4

The Power of Choice is Yours

Engineered to support any NVMe M.2 2230, 2242, or 2280 SSD, this compact powerhouse gives you the ultimate flexibility to choose the drive you want today—including OWC Aura SSDs with up to a massive 8.0TB capacity each. When tomorrow’s 16TB and larger drives hit the scene, you can easily boost your Express 4M2’s capacity.

One Cool RAID for Diverse Workflows

High speed backups, multiple media card offloads, and intense RAW photo and 8K video editing sessions mean one thing…Heat. You can put aside any thermal throttling and noise concerns because the Express 4M2 utilizes a heat dissipating solid aluminum body along with smart, adaptive fans that activate only when needed or under heavy load. Diversity of use also means being able to easily work cross-platform with Macs and PCs. We help you keep your cool in mixed environments with our MacDrive software (sold separately).

Express 4M2 is ideal for:

DITs and Filmmakers wanting to build an affordable yet high-performance NVMe SSD RAID with up to 32TB of capacity, RAID 5 capabilities, and the ability to deliver maximum offload speeds and thermal stability when backing up media cards from multiple cameras on set.
Professional Video Editors, VFX Artists, Colorists, and High-Volume Photographers seeking an easy DIY assemble high-performance NVMe SSD RAID to handle demanding post-production and editing workflows including 8K RAW video, VFX compositing work, multicam sequences in 4K RAW or ProRes video, and batch editing ultra-high-resolution pictures.
Anyone looking for a lower cost RAID option to the award-winning four NVMe M.2 based OWC ThunderBlade and are willing to accept the Express 4M2’s larger form factor, fan cooling, no additional connectivity ports, and no ballistic shipping case for shuttle use.

More Powerful with SoftRAID

Need more power and protection? Choose a solution that includes OWC's powerful SoftRAID RAID software.

SoftRAID is the most powerful, intuitive software RAID utility on the market. Multiple RAID levels let you select the RAID level that fits you or your project’s needs best. If you need maximum volume capacity, optimum drive performance, data protection, or a combination of attributes, SoftRAID has you covered.

Packed with features like drive validation, verification and failure prediction—SoftRAID includes features you simply don’t get with hardware RAID. It’s like having a datacenter on your desktop! From home users looking to protect photos and documents to professionals needing to protect and quickly access projects, SoftRAID is the perfect solution.

Dive deeper into the benefits of OWC SoftRAID »

Try SoftRAID COMPLETELY FREE for 14 Days

Start protecting yourself and your data today! Get all of SoftRAID's great disk checking and monitoring features, plus the fastest and most efficient software RAID there is.

Download and try OWC SoftRAID for FREE »

Your Data’s Reliability is Our #1 Priority

Anyone can put a bunch of components in a housing and call it an enclosure or a drive. OWC is not just anyone. We’re a group of filmmakers, musicians, designers, content creators, and parents just like you wanting to capture and preserve that irreplaceable moment. Our data storage products go through countless hours of ongoing development testing and certification processes. We then subject them to extreme real-world abuses. The priority for some storage devices is to be a mass-produced, lowest price commodity. We do it differently because the reliability of your data and the longevity of an OWC product is priority #1.

A individual is working on a story board and using editing software in the background

OWC Aura SSDs: The perfect match for Express 4M2

Combine Express 4M2 with its perfect performance match – four blazing fast OWC Aura NVMe M.2 SSDs - and enjoy incredible transfer speeds, capacity, and most importantly, OWC reliability you can count on.

OWC USB-C (40Gb/s) Cable Included

OWC Express 4M2 comes with a 0.7M (28") OWC USB-C (40Gb/s) Cable. But if your workflow demands a different length to make the connection, OWC USB4 Active Optical Cables are the perfect choice.

Discover the OWC Difference

Since 1988, our mission has focused on maximizing the usefulness and longevity of your technology investment. Our business operations share that same sustainability commitment. As the first 100% on-site wind powered technology manufacturer/distributor in the U.S., we now generate excess power. 97% of solid waste is recycled. These and other actions have resulted in our headquarters being Energy Star® and LEED® Platinum certified. Learn more about our passion for the planet we share at macsales.com/green

Drive not included. Performance results will vary depending on user installed drive. 3200MB/s performance based on testing a Software RAID 0 4x2TB OWC Aura Pro IV equipped Express 4M2 connected to a MacBook Pro (16-inch, 2021) running AJA System Test (4K-Full resolution, 64GB file size, 16bit RGBA codec, single file test).
- Single drive performance up to 1600MB/s.
- Intel Mac system users connected over Thunderbolt 3 will experience Write Speeds up to 1000MB/s and Read Speeds up to 2500MB/s.
For best performance, the USB mode switch should be kept in the factory USB4 40Gb/s setting when connecting the Express 4M2 to the following systems:
- Mac: Thunderbolt 5, Thunderbolt 4, USB4, or Thunderbolt 3 Intel based systems running macOS 15.x and later.
- Windows: Thunderbolt 5, Thunderbolt 4, and USB4 systems.
To ensure compatible performance, the USB3.2 10Gb/s mode should be selected when connecting the Express 4M2 to the following systems:
- Mac: Thunderbolt 3 Intel based systems running macOS 14.x or earlier.
- Windows: Thunderbolt 3 and USB 3.2 10Gb/s systems.