1. Product Overview
The Alxum Y-ST03004 USB-C Dual Bay Dock is a professional-grade solution for dual-drive management and offline cloning. Featuring USB 3.0 Type-C (5Gbps) and UASP acceleration, this dock delivers up to 30% faster transfers than standard USB 3.0, perfect for data backups and drive duplication. It supports simultaneous access to two 2.5"/3.5" SATA drives (HDD/SSD) and offers offline cloning capabilities without needing a computer.
Key Features:
- Dual-Drive Operation: Simultaneously access two 2.5"/3.5" SATA drives (HDD/SSD).
- Offline Cloning: Clone between drives without a computer.
- High-Speed Performance: USB 3.0 Type-C (5Gbps) + SATA III (6Gbps) with UASP support for up to 30% faster speeds.
- Intelligent Design: LED progress indicators (25%-100% cloning status) and auto sleep mode after 30 minutes of inactivity.
- Universal Compatibility: Works with Windows XP-10, macOS 10.6+, and Linux.
- Type-C Connectivity: Features a Type-C connector for reversible plug orientation.
2. Package Contents
Please check the box for the following items:
- 1 x USB3.0 to SATA Dual Bay Docking Station
- 1 x 12V/3A Power Adapter
- 1 x USB C to USB C Cable with USB A Adapter (1.5m length)
- 1 x User Manual
3. Product Schematic Diagram

- Green LED Light: Lights on when power is connected. Flashes on for 1 second and off for 3 seconds when entering sleep mode.
- Clone Button
- Blue LED Light: Indicates cloning progress. Starts flashing from 25%, lights on when cloning is completed.
- Yellow LED Light: Flashing when reading or writing on Disk A.
- Yellow LED Light: Flashing when reading or writing on Disk B.
- Disk A (Source)
- Disk B (Destination)
- USB3.0 Type-C Port (Upstream)
- DC12V Power Jack
- On/Off Switch
4. Setup Instructions
4.1 Connecting the Docking Station
- Connect the 12V/3A power adapter to the DC12V Power Jack (I) on the back of the docking station.
- Connect the USB-C cable to the USB3.0 Type-C Port (H) on the back of the docking station.
- Connect the other end of the USB-C cable to your computer's USB-C or USB-A port (using the provided adapter if necessary).
- Flip the On/Off Switch (J) to the 'ON' position. The Green LED Light (A) will illuminate.

4.2 Inserting Hard Drives
- Ensure the docking station is powered off or disconnected from the computer if not hot-swapping.
- Gently insert your 2.5" or 3.5" SATA HDD/SSD into Disk A (F) and/or Disk B (G) slots until they are firmly seated.
- If using 3.5" drives, ensure the 12V/3A power adapter is connected. 2.5" drives typically do not require external power.

5. Operating Instructions
5.1 Online Mode (Data Transfer)
Once connected to your computer and powered on, the inserted hard drives will appear as external storage devices. You can now read and write data to them as you would with any other external drive.

5.2 Offline Cloning
The offline cloning function allows you to duplicate a source hard drive (Disk A) to a target hard drive (Disk B) without needing a computer. This is ideal for data backup or system migration.

Important Notes for Offline Cloning:
- Insert the source hard disk into the Disk A position and the target hard disk into the Disk B position.
- The capacity of the target hard disk (Disk B) must be equal to or greater than the source hard disk (Disk A).
- Once cloning starts, Disk B will be overwritten by Disk A. Ensure that any data on Disk B is backed up if needed, as Alxum shall not be responsible or liable for any loss or damage of any kind incurred as a result of the use of this product.
Steps for Offline Cloning:
- Ensure the docking station is powered off.
- Insert the source hard disk into Disk A (F) and the target hard disk into Disk B (G).
- Connect the power adapter and turn on the docking station using the On/Off Switch (J). The Green LED (A) and A/B indicator lights should turn on.
- Wait for 1-2 seconds for the drives to be buffered.
- Press and hold the Clone Button (B) for 3 seconds until the '100%' blue LED light (C) illuminates.
- Release the Clone Button, then press it again to start the cloning process.
- During cloning, the 25%, 50%, 75%, and 100% blue LED indicators (C) will flash in sequence.
- Once cloning is complete, all blue LED indicators will light up steadily.
5.3 LED Indicators

- Green LED (Power): Solid green when powered on. Flashes when entering sleep mode.
- Yellow LED (Disk A/B): Flashes when reading or writing on the respective disk.
- Blue LEDs (25%, 50%, 75%, 100%): Indicate cloning progress. Flash during cloning, solid when cloning stage is complete.
5.4 Auto-Sleep Function
The docking station will automatically enter sleep mode after 30 minutes of inactivity. This feature helps save power and extends the lifespan of your hard drives.
6. Maintenance
- Keep the docking station clean and free from dust. Use a soft, dry cloth for cleaning.
- Avoid exposing the device to extreme temperatures, humidity, or direct sunlight.
- Do not disassemble the device, as this will void the warranty.
7. Troubleshooting (FAQ)
- Q: What if offline cloning does not start?
- A: Please check that the capacity of the target hard disk (Disk B) is equal to or greater than the source hard disk (Disk A).
- Q: What if LED lights stop flashing during cloning?
- A: This may indicate bad sectors, a virus, or an error in the hard disks, which can cause cloning to fail.
- Q: After offline cloning, Disk B is in an offline state. How can I access it?
- A: To bring Disk B online and read its contents, go to 'Computer Management' > 'Storage' > 'Disk Management' on your computer.
- Q: Windows XP supports a maximum of 2TB hard disk capacity. What if I have a hard disk larger than 2TB?
- A: We suggest using Windows Vista (64-bit) or above, and partitioning the hard disk to GPT format.
8. Specifications
| Feature | Detail |
|---|---|
| Model Number | Y-ST03004 (AX-S300A-UK) |
| Hard Disk Types Supported | 2.5" HDD, 3.5" HDD, 2.5" SATA HDD, 3.5" SATA HDD (SATA I/II/III) |
| Supporting Hard Drive Capacity | Up to 32TB (per bay, 18TB mentioned in image) |
| External Interface | USB 3.0 Type-C (Uplink) |
| Internal Interface | SATA*2 (Downstream) |
| Transmission Bandwidth | Up to 6Gbps |
| Power Adapter | DC 12V/3A (5.5*2.5mm DC port) |
| Product Size | 115mm x 115mm x 100mm (4.5in x 4.5in x 3.4in) |
| Case Material | Plastic |
| Compatible Systems | Windows XP/Vista/7/8/8.1/10 (32/64 bit), macOS, Linux |
| Certifications | CE, FCC, RoHS, UKCA, UL Listed |

9. Warranty & Support
- 2-Year Warranty: The product comes with a 2-year warranty from the date of purchase.
- Lifetime Technical Support: Alxum provides lifetime technical support for this product.
- 24H Customer Service Support: For any inquiries or issues, please contact support@alxum.com.
10. User Tips
- For optimal performance, ensure your operating system and drivers are up to date.
- When using for data transfer, connect directly to a USB 3.0 or higher port on your computer for maximum speed.
- Consider using the docking station to expand storage for gaming consoles or to directly play media files from hard drives on your TV.
11. Additional Resources
A detailed user manual in PDF format is available for download. You can access it via the following link: Alxum USB-C Dual Bay Docking Station User Manual (PDF).
