We're sorry, but this item is no longer for sale. However, there may be more External Drives & Enclosures items available.
We recommend OWC Express 1M2 USB4 (40Gb/s) Bus-Powered Portable External Storage Enclosure for NVMe M.2 SSDs (Mfr P/N: US4EXP1M2) from OWC for $119.99 as a suitable alternative.
OWC Express 4M2
Four-Slot Thunderbolt (40Gb/s) NVMe M.2 SSD Enclosure with SoftRAID for NVMe M.2 2280 SSDs
Mfr P/N: TB3EX4M2SL OWC SKU: OWCTB3EX4M2SL
Infinitely configurable. Infinitely reconfigurable.
- Four NVMe M.2 SSD slots - Add up to 32TB of storage
- Up to 2800MB/s
- Compact design
- Includes SoftRAID: robust software for creating, monitoring, and managing advanced RAID sets
- Thunderbolt Certified for Mac and Windows
- Includes Thunderbolt (USB-C) cable
- 1 Year OWC Limited Warranty
- When using Express 4M2 with Mac Studio (M2 Max or M2 Ultra) or Mac Pro (M2 Ultra), some drives may require macOS 13.5 or later for proper operation.
Pint-Sized Powerhouse
Built Smaller and Faster from Input by Pros Like You
Game-Changing NVMe SSD Performance
DisplayPort
Multi-Drive
The Most Powerful RAID Tool on the Planet.
- 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
Connect to Thunderbolt and Thunderbolt 2 Systems with Ease
OWC Thunderbolt cable
Quality You Can Trust
- Thunderbolt 2/Thunderbolt compatibility requires a certified Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) adapter and a Thunderbolt 2 cable (not included). This configuration provides data transfer at up to 20Gb/s but does not support notebook charging.
- SoftRAID works with macOS 10.14+, Windows 10+, and Windows Server 2019/2022. M1 Macs require macOS 11.3 or later.
- SoftRAID is licensed per computer.
Includes
- (1) OWC Express 4M2 External Storage Enclosure
- (1) 0.7M (28") Thunderbolt (USB-C) Cable
- (1) Power Supply and Power Cable
- (4) SSD Mounting Screws (pre-affixed to the circuit board, opposite the M.2 connectors)
- (1) Quick Start Guide for OWC Express 4M2
- (1) Assembly Manual & User Guide for OWC Express 4M2
- (1) 3 Years of SoftRAID Premium Access (License located on device)
- (1) Quick Start Guide for OWC SoftRAID (Digital)
- 1 Year OWC Limited Warranty
Need an additional power supply? Secondary/replacement power supplies are also available.
Specs
Drive Bays
- 4 bays supporting: M.2 drives
- Supports single-sided and double-sided M.2 2280 "M Key" drives
- NVMe SSDs with a heatsink are not supported.
- Each bay offers PCIe 3.0 x1 performance.
Hot Plug Support
- Yes
Boot Support
- All four drive bays are bootable on macOS. SSDs with 512 byte sectors require macOS 10.13 or later. Boot Camp is not supported.
RAID Capable
- Yes
RAID Levels Supported
- RAID 0
- RAID 1
- RAID 4
- RAID 5
- RAID 10
- JBOD
RAID Features
- Software RAID
Device Ports
- (1) Host Port - Thunderbolt 3 (USB-C) up to 40Gb/s (5000MB/s)
- (1) Thunderbolt 3 (USB-C) Port
- (1) DisplayPort Port
Power Delivery
- Two Thunderbolt 3 ports with 15W power delivery each.
Display Support
- Up to one 4K display @ 60Hz,
- or one 4K display @ 30Hz,
- or two 4K displays @ 60Hz
Display Support by Port
- DisplayPort 1.2: Up to 4K @ 60Hz
Data Transfer Rate (Maximum)
- Thunderbolt 3 : Up to 40Gb/s (or 5000MB/s)
Chipset / Controller
- (1) Thunderbolt 3 - Alpine Ridge DSL6540
MTBF (Mean Time Between Failures)
- Varies depending on drive mechanism installed
Contact Start Stops
- Varies depending on drive mechanism installed
Host Interface Requirements
- Thunderbolt (USB-C) port (backward compatible with Thunderbolt 2/Thunderbolt1)
Mac OS Compatibility
- macOS 10.12 Sierra
- macOS 10.13 High Sierra
- macOS 10.14 Mojave
- macOS 10.15 Catalina
- macOS 11.x Big Sur
- macOS 12.x Monterey
- macOS 13.x Ventura
- macOS 14.x Sonoma
- macOS 15.x Sequoia
PC OS Compatibility
- Windows 10 32-bit Edition
- Windows 10 64-bit Edition
- Windows Server 2019
- Windows Server 2016
- Windows Server 2022
- Windows 11
Driver Required
- No
Other Requirements
- When using Express 4M2 with Mac Studio (M2 Max or M2 Ultra) or Mac Pro (M2 Ultra), some drives may require macOS 13.5 or later for proper operation.
- When using one or more SSDs with 512 byte sectors, macOS 10.13 or later is required.
- SoftRAID works with macOS 10.14 or later and Windows 10 or later. SoftRAID is licensed per computer. The SoftRAID serial number will work with both Mac and Windows but can only be active on one computer at a time. Additional seats can be purchased. RAID 4/1+0 (10) are currently Mac only at this time.
External Power Adapter
- Yes
Power Supply
- External UL-listed universal auto-switching power supply
- Need an additional power supply? Secondary/replacement power supplies are also available.
AC Input
- 100-240V, 50-60Hz, 1-2A
DC Output
- +12V, 6A
Wattage
- 72W
Cooling
- (1) 60mm 2,800RPM cooling fan
Security Slot
- No
Power/Activity LED
- Yes
Housing Color
- Black
Housing Material
- Aluminum
Dimensions
- Height: 6.0 cm (2.4 in)
- Length: 11.3 cm (4.4 in)
- Width: 13.6 cm (5.4 in)
Weight
- 800.0 g (1.76 lbs)
Certifications
- CE
- FCC
Ambient Temperature
- Operating: 32°F to 104°F (0°C to 40°C)
- Non-Operating: -4°F to 158°F (-20°C to 70°C)
Altitude
- Operating: -304.8 m to 3,048.0 m (-1,000 ft to 10,000 ft)
- Non-Operating: -304.8 m to 12,192.0 m (-1,000 ft to 40,000 ft)
- Thunderbolt 2/Thunderbolt compatibility requires a certified Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) adapter and a Thunderbolt 2 cable (not included). This configuration provides data transfer at up to 20Gb/s but does not support notebook charging.
- SoftRAID works with macOS 10.14 or later and Windows 10 or later. M1 Macs require macOS 11.3 or later. SoftRAID is licensed per computer.
- SoftRAID works with macOS 10.14+, Windows 10+, and Windows Server 2019/2022. M1 Macs require macOS 11.3 or later.
- SoftRAID is licensed per computer.
- Maximum single drive performance is 817 MB/s Reads and 711MB/s Writes due to the bandwidth of the 1X PCIe3.0 bus.
- When installed, the following SSDs will only be compatible with Windows 10 systems: Hynix Gold P31, Samsung PM981a
- Does not support Dual-Mode DisplayPort (DP++), however it does support Multi-Stream Transport (MST) in Windows 10.
- Dual display support, including available resolution and refresh rates, is dependent on host hardware and drivers.
- Apple silicon M1/M2/M3 Pro, M1/M2/M3 Max, and M1/M2 Ultra Mac models, Apple Intel-based Mac models, and Thunderbolt 4 PCs can support up to two displays at up to 4K @ 60Hz via Thunderbolt.
- Apple silicon M1/M2/M3 Mac models can support one external display up to 4K @ 60Hz via Thunderbolt. - The following Apple silicon M1/M2/M3 Mac models support a single display over a Thunderbolt port:
- MacBook Pro (14-inch, M3, 2023)
- MacBook Pro (13-inch, M1, 2020) - MacBookPro17,1
- MacBook Pro (13-inch, M2, 2022) - Mac14,7
- MacBook Air (M1, 2020) - MacBookAir10,1
- MacBook Air (M2, 2022) - Mac14,2
- Mac mini (M1, 2020) - Macmini9,1 - The following Mac models provide only partial support for DisplayPort 1.4, including limiting resolution to 5K or 6K at 60Hz. Please review Apple's display specifications for your specific Mac to determine the maximum supported resolution and color depth:
- MacBook Pro (15-inch, 2018) - MacBookPro15,1
- MacBook Pro (13-inch, 2018, Four Thunderbolt 3 ports) - MacBookPro15,2
- MacBook Pro (13-inch, 2019, Four Thunderbolt 3 ports) - MacBookPro15,2
- MacBook Pro (15-inch, 2019) - MacBookPro15,1 and MacBookPro15,3
- MacBook Pro (13-inch, 2019, Two Thunderbolt 3 ports) - MacBookPro15,4
- MacBook Pro (16-inch, 2019) - MacBookPro16,1 and MacBookPro16,4
- MacBook Pro (13-inch, 2020, Four Thunderbolt 3 ports) - MacBookPro16,2
- MacBook Pro (13-inch, 2020, Two Thunderbolt 3 ports) - MacBookPro16,3
- MacBook Air (Retina, 13-inch, 2018) - MacBookAir8,1
- MacBook Air (Retina, 13-inch, 2019) - MacBookAir8,2
- MacBook Air (Retina, 13-inch, 2020) - MacBookAir9,1
- iMac (Retina 5K, 27-inch, 2019) - iMac19,1
- iMac (Retina 4K, 21.5-inch, 2019) - iMac19,2
- iMac (Retina 5K, 27-inch, 2020) - iMac20,1 and iMac20,2
- Mac mini (2018) - Macmini8,1
- Mac Pro (2019) - MacPro7,1
- Mac Pro (Rack, 2019) - MacPro7,1 - Multiple drives will not be recognized by a Thunderbolt 4 PC connected over a Thunderbolt 4 port when using Aura Ultra IV SSDs with the Express 4M2.
- When using Express 4M2 with Mac Studio (M2 Max or M2 Ultra) or Mac Pro (M2 Ultra), some drives may require macOS 13.5 or later for proper operation.
Compatibility & Installation Videos
MacBook Pro


































Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.
MacBook Air










Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.










Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.

Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.
Mac Pro








Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.
Mac Studio



Mac mini





Requires Thunderbolt 3 (USB-C) to Thunderbolt 2 (mDP) Adapter and Thunderbolt 2 cable.
PC Compatible

PC must have a compatible Thunderbolt port
Products
Videos
M.2 SSD Install Video
Learn More
Customer Reviews
This worked great. Easy to install the (not included) drives. Plug and Play. Super fast.
I would recommend this product to a friend!
- Reviewer:Reviewer3776135135
Thank you so much for your fantastic review! We’re thrilled to hear that everything worked great for you and that the installation was a breeze. It's awesome to know you’re enjoying the plug-and-play convenience and speed! Your satisfaction means the world to us. Keep enjoying your setup!
Very happy with my new 4 x 4TB array hosting content and VMs, was extremely easy to setup using SoftRAID
I would recommend this product to a friend!
- Reviewer:fhlipzero
Wow, thank you so much for your fantastic review! We're thrilled to hear that you're loving your new 4 x 4TB array and that it’s working great for your content and VMs. It's awesome to know that the setup with SoftRAID was a breeze for you! We appreciate your feedback and can’t wait to see what you do with it next. Enjoy the speed and reliability! Please feel free to contact us if you have any further questions, comments, or concerns. https://eshop.macsales.com/Service/
I have complete trust in OWC and have been a customer for many years. I bought the OWC Express 4M2 to replace a HDD RAID that was a serious bottleneck in my film editing workflow. The 4M2, filled with 32Gb of Sandisk WD Black SSDs is a blazing fast drive. The performance is a remarkable upgrade. No bottlenecks now.
I would recommend this product to a friend!
- Reviewer:SuccessfulRaven-97732
Wow! We're thrilled to hear how the OWC Express 4M2 has transformed your film editing workflow! It's fantastic to know that after years of trust in us, you've found such a powerful upgrade to eliminate those bottlenecks. Your experience truly energizes our commitment to providing top-notch solutions. Thank you for sharing your excitement and being a valued part of the OWC family! Enjoy that blazing fast performance!