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SK-2520 U3.1

akitio-sk2520-u31-angle-thumb SK-2520 U3.1 front SK-2520 U3.1 back SK-2520 U3.1 size

USB 3.1 10G
USB Type-C connector
Bus powered
Power delivery (15W)
Hardware RAID controller

SK-2520 U3.1

The SK-2520 U3.1 is a dual-bay storage enclosure with hardware RAID, designed for two 2.5-inch SATA drives. In combination with two striped SSDs and its fast SuperSpeed USB 3.1 10Gbps (USB 3.1 Gen 2) interface, this bus powered storage drive can deliver speeds up to around 800-900 MB/s.

  • Configurable hardware RAID controller (Non-RAID, RAID 0, RAID 1, SPAN)
  • SuperSpeed USB 10Gbps (USB 3.1 Gen 2) interface
  • Supports Universal Attached SCSI Protocol (UASP)
  • USB power delivery provides 15W of power to compatible laptops
  • Bus powered when external power supply is not connected
  • Designed for two 2.5" SATA drives up to 15mm
  • Supports SATA 6Gb/s (SATA-III) drives
  • Reversible USB Type-C connector
  • Durable all aluminum enclosure
  • Fanless

SuperSpeed USB 10Gbps (USB 3.1 Gen 2)

By incorporating the latest SuperSpeed USB 10Gbps (USB 3.1 Gen 2) technology, the SK-2520 U3.1 is able to deliver up to twice the speed of the USB 3.1 Gen 1 interface which runs at only 5Gbps. At the same time, with a corresponding USB-C to USB adapter cable, the device is still backwards compatible with the widely used USB 3.0 and USB 2.0 technology.

AKiTiO SK-2520 U3.1 features

Reversible USB Type-C™ Connector with USB Power Delivery (PD)

The reversible USB Type-C (USB-C) connector enhances ease of use for connecting USB devices with a focus on minimizing user confusion for plug and cable orientation. When the external power adapter is plugged into the device the SK-2520 U3.1 supports power delivery (PD) over USB-C, providing 15W of power to laptops like the MacBook Pro (late 2016) that support charging from a 5V/3A power source. This allows you to work with the external drive without the battery levels of your laptop dropping even when the laptop is not plugged into any other power source.

AKiTiO SK-2520 U3.1 detailed view

USB Bus Power

This portable and compact USB drive can run on bus power alone without the need for an extra power adapter if the host computer provides sufficient bus power and the drive's power consumption stays below 7W per drive. An external power adapter is included if bus power is insufficient.

SK-2520 U3.1 detailed view open case

Hardware RAID Controller

With the built-in hardware RAID controller you can mirror the drives with RAID 1 as a reliable backup for your important data, stripe the drives with RAID 0 for optimal performance and maximum transfer rates or you can select SPAN to combine the drives for large storage capacities. Even individually with Non-RAID, the SATA 6Gb/s interface allows each drive to run at full SATA-III speeds.

SK-2520 U3.1 hardware RAID controller


Results will vary depending on the test environment and the drives but for the best performance, install one or two SATA 6Gb/s SSDs and connect the device to a computer that supports USB 3.1 Gen 2 at 10Gbps.

When connected to a computer that supports only USB 3.1 Gen 1 at 5Gbps or USB 3.0, the speed is limited by the interface to around 400 MB/s. For traditional spinning hard disk drives (HDDs), the transfer rate is limited by the drive to around 100 MB/s.


SK-2520 U3.1

  • SK25-U31AS-AKTU (no drives)

  • CE

  • FCC

  • VCCI

  • BSMI

  • 2-year limited warranty

  • High quality aluminum for optimized heat dissipation

  • Up to two 2.5" SATA 6Gb/s SSDs or HDDs

  • Height 7mm - 15mm

  • For RAID 0 & 1, two hard drives of identical capacity are recommended

  • Non-RAID

  • RAID 0 striping

  • RAID 1 mirroring

  • SPAN

  • 1x USB-C port supporting USB 3.1 Gen 2 and power delivery (5V/3A only)

  • USB 3.1 Gen 2 up to 10Gbps

  • USB 3.1 Gen 1 up to 5Gbps

  • Windows 7 or above

  • Computer with USB Type-C connector or otherwise a USB-C to USB Type-A adapter cable is required (not included)

  • mac OS 10.12.4 or above

  • Computer with USB Type-C connector or otherwise a USB-C to USB Type-A adapter cable is required (not included)

  • Operating Temperature: 5°C ~ 35°C

  • Storage Temperature: -20°C ~ 60°C

  • Relative Humidity: 5% ~ 95% (non-condensing)

  • USB bus power 5V/3A (host computer has to provide sufficient USB bus power)

  • External power supply (UL, cUL, CE, TUV approved)

  • Input: AC 100-240V, 50-60Hz

  • Output: DC +12V/3A


  • 6.1 inches x 6 inches x 0.87 inches

  • 15.5cm x 15.2cm x 2.2cm

  • SK-2520 U3.1

  • USB-C to USB-C cable (1 m)

  • Power adapter

  • Setup guide

  • Retail Box Size: 9.17 x 7.2 x 3.54 in. (23.3 x 18.3 x 9 cm)

  • Carton Size (10pcs per carton): 18.9 x 15.4 x 10.04 in. (48 x 39.1 x 25.5 cm)

  • Gross Weight: 0.95 kg (retail box), 10.4 kg (carton)

  • For best performance and power delivery (PD), use the included USB-C cable.

  • This enclosure is NOT compatible with drives that require 12V (e.g. Seagate Constellation or WD VelociRaptor).

  • If bus power is insufficient (e.g. for two drives with a power consumption of more than 7W per drive), the power adapter is required. Otherwise, the data or the disk may be damaged.

  • This product is backwards compatible with USB 3.0 but it requires a separate USB-C to USB adapter cable.

  • This product has components or design elements that are patented or patent pending.


If you’re a 12-inch MacBook owner who happens to have a couple of spare SSDs collecting dust around the house, then the SK-2520 is an enclosure that can put those drives to good use. In that situation, I think the Akitio enclosure would be an ideal purchase at just over $100. Read More...

Jeff Benjamin - 9TO5MAC (February 23, 2018)

When the AC power adapter is not connected, the AKiTiO SK-2520 U3.1 can directly draw power from your computer, tablet, or phone as long as each SATA drive you put inside the AKiTiO SK-2520 U3.1 consumes less than 7W and the computer, tablet, or phone is able to provide 15 watts of power through the USB Power Delivery protocol. Read More...

GTrusted (December 21, 2017)

Parts List

Part No.QtyDescription
E11-1111036017 1 Power adapter (12V/3A)
E10-D040022315 1 2 US plug adapter
E10-D040032304 0 2 UK plug adapter
E10-D040022317 0 2 EU plug adapter (Type C)
E10-D040022314 0 2 AU plug adapter
E11-1111036A00 0 2 CN power adapter (12V/3A) and plug adapter
E10-D040022322 0 2 KR plug adapter
E14-324D100003 1 USB-C to USB-C cable (1m)
E19-1001290001 4 Rubber feet
E16-1438320006 4 Flat head screws for 2.5" drives (M3, 4mm)
E16-1438320000 2 Flat head screws for case back (M3, 6mm)
E16-1198005720 2 Flat head screws for case front (M3, 5mm)

(1) Optional part, not included in standard package.
(2) Includes only one type of plug, depending on the country of purchase.

Remarks: Included parts and components may vary and can change without prior notice!