UGREEN 30333 USB 3.0 4-in-1 SD/TF/CF/MS Card Reader, 0.5m
Overview
UGREEN 30333 is a desktop-friendly USB-A 3.0 reader with four separate card-family slots. This model guide separates connector bandwidth from real card performance and explains every important compatibility boundary before you move valuable files.
- SKU 30333
What it does well.
Key features
Reader role. a desktop-friendly USB-A 3.0 reader with four separate card-family slots.
Host connection. integrated USB-A 3.0 cable, approximately 0.5m / 19.5 inches.
Card layout. 1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick.
Practical speed. UHS-I-class SD performance up to about 104MB/s is stated in official regional material; CF and MS performance depends on the card technology.
Model check: Similar-looking UGREEN readers can differ in host plug, card protocol, simultaneous access, extra USB ports and charging. Match SKU 30333 rather than buying by appearance alone.
Ports, slots and connection map
Host side: integrated USB-A 3.0 cable, approximately 0.5m / 19.5 inches.
Reader and accessory side: 1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick.
Extra function: Blue LED indicates connection/activity. The long cable reduces strain and avoids blocking adjacent ports.
Direction rule: A card reader is a host accessory. It must connect to a device that can act as a USB host; connecting two accessories together does not create a host.
Speed explained without the marketing blur
USB/interface ceiling. Up to 5Gbps USB 3.0 signalling, backward compatible with slower USB modes.
Memory-card ceiling. UHS-I-class SD performance up to about 104MB/s is stated in official regional material; CF and MS performance depends on the card technology.
UHS generation. UHS-I workflow. A UHS-II SD card may be accepted only at the reader/card mode actually negotiated; no UHS-II speed claim is made.
Real-world result. The slowest link wins: card, slot mode, reader controller, host port, file system, thermal state, file sizes and simultaneous activity all matter.
Never equate 5Gbps or 10Gbps with card speed. USB values describe theoretical link signalling. SD and microSD media usually operate at much lower sustained rates, and many small files transfer more slowly than one large sequential file.
Card formats, capacity and file systems
Supported card families. SD, SDHC, SDXC, MMC/RS-MMC; microSD/TF, microSDHC, microSDXC; CompactFlash Type I; compatible Memory Stick/PRO families.
Capacity boundary.
File-system caveat. The card must use a format the host understands. exFAT is common for large removable media; FAT32 has file-size limits; NTFS and vendor-specific formats may not mount on phones/tablets.
Write-protect reminder. A full-size SD card with its lock tab engaged may be readable but not writable. The reader cannot override the card's mechanical write-protect state.
Simultaneous access and shared-resource behaviour
The UGREEN gallery and regional product copy support reading and writing all four installed cards at the same time. Total bandwidth is shared.
Shared bandwidth. Two cards or attached peripherals divide the bandwidth available through the single host connection.
Shared power. Bus-powered readers and USB peripherals depend on host power. High-draw drives may disconnect or fail to mount without an appropriate powered path.
Copying card-to-card. The computer or mobile host mediates the copy. The reader is not an autonomous duplicator and does not copy files when disconnected from a host.
Safest workflow. For irreplaceable media, copy one card, verify the files, create a second backup and only then erase or reformat the original.
Compatible devices and systems
Compatible device class: desktop and laptop computers with a USB-A host port.
Operating systems: Windows, macOS, Linux and ChromeOS with USB mass-storage support..
Mobile rule: Direct phone/tablet use is not the intended path. A separate powered/OTG adapter may still face host, file-system and power limits.
USB-C is only a shape. A USB-C port can be charging-only, data-capable, OTG-capable or video-capable. Confirm the host function.
Apps and permissions. On phones/tablets, use Files, Photos or the manufacturer's supported file manager and allow removable-storage access when prompted.
Cases and clearance. A thick case can prevent full plug insertion. Remove it temporarily rather than forcing the connector.
Managed devices. Corporate policy, encrypted cards or restricted mobile profiles can block removable media even when hardware is compatible.
Use scenarios
Scenario 1. Recover photos from legacy CF Type I cards.
Scenario 2. Import SD and microSD camera media.
Scenario 3. Read Memory Stick media from older devices.
Scenario 4. Access four supported card families in one desktop workflow.
Setup and usability guidance
- Confirm SKU 30333, the required host connector and the card format before insertion.
- If using a phone or tablet, enable or confirm OTG/USB-host storage and make sure the battery has enough charge.
- Insert the memory card straight into its matching slot in the orientation shown by the slot label. Never force it.
- Connect the reader to the host. Wait for the removable volume to appear in Files, Finder, File Explorer or the supported mobile app.
- Copy a small test file first. Then start the main transfer and keep the device, cable and cards still.
- Verify copied folders, file counts and several representative files before treating the transfer as a backup.
- Use Eject or Unmount, wait for activity to finish, then disconnect by the connector housing rather than the cable.
What this product does
- a desktop-friendly USB-A 3.0 reader with four separate card-family slots.
- Provides 1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick.
- Works within the documented speed and compatibility limits.
- Supports the stated host and card families when the operating system can mount them.
- not for CompactFlash Type II, CFast, CFexpress, XQD, UHS-II speed, charging, video output or data recovery.
- It does not repair corrupted media, recover deleted files or guarantee that damaged cards will mount.
- It does not make one copy into a backup; keep another copy on separate storage.
- It does not guarantee every illustrated device, card capacity or speed without the required host capability.
What to do
Do: label cards. Separate blank, active and backed-up cards. Locking or labelling completed media prevents accidental erasure.
Do: verify before erasing. Open several copied files and compare counts or checksums for critical work.
Do: keep connectors clean. Use a dry, dust-free environment and store the reader where slot contacts are protected.
Do: eject safely. Unmount every active volume and wait for activity to stop before removal.
Do not: remove during writing. Disconnecting during import, deletion, formatting or metadata updates can corrupt the file system.
Do not: force media. Wrong orientation or the wrong card family can bend contacts or crack the card.
Do not: format the wrong disk. Confirm the volume name, capacity and path before erase or format operations.
Do not: trust one copy. Portable cards fail, get lost and can be overwritten. Maintain a separate backup.
Warnings and limitations
Heat and moisture: keep the reader dry and ventilated. Mild warmth during sustained transfer can be normal; disconnect if there is unusual heat, smell, deformation or repeated resets.
Power: Blue LED indicates connection/activity. The long cable reduces strain and avoids blocking adjacent ports.
Card handling: do not touch contacts, bend cards, use cracked adapters or insert nested adapters that do not fit cleanly.
Formatting: formatting deletes the file-system index and can make recovery difficult. Back up first and confirm the target device's preferred format.
Critical data: no reader can guarantee recovery from failing media. Stop repeated write attempts on a card showing errors and seek professional recovery help if the files are irreplaceable.
Troubleshooting
Card does not appear. Reseat the card and reader, confirm slot orientation, test one card at a time, remove an obstructing case and check OTG/file-system support.
Card is read-only. Check the SD lock tab, operating-system permissions, card health and whether the file system was mounted read-only after errors.
Transfer is slower than expected. Use one card, a direct high-speed host port and large sequential files; confirm the card's own sustained rating and negotiated UHS mode.
Reader disconnects. Remove high-power USB peripherals, connect a suitable PD/powered path where this model supports it, and avoid loose extensions.
Phone cannot see files. Use the Files/Photos app, enable OTG, grant storage permission and verify the card uses a phone-supported format such as exFAT/FAT32.
Copied file will not open. Compare the original, copy again to a different destination and stop using a card that reports I/O, CRC or corruption errors.
Final model check
Confirm SKU 30333, integrated USB-A 3.0 cable, approximately 0.5m / 19.5 inches, and 1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick. Then match the UHS mode, capacity, simultaneous-access rule and mobile/charging requirements before ordering.
At a glance.
- Brand / SKU
- UGREEN 30333
- Product role
- a desktop-friendly USB-A 3.0 reader with four separate card-family slots
- Host connection
- integrated USB-A 3.0 cable, approximately 0.5m / 19.5 inches
- Slots / ports
- 1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick
- Simultaneous behaviour
- The UGREEN gallery and regional product copy support reading and writing all four installed cards at the same time. Total bandwidth is shared.
- Interface ceiling
- Up to 5Gbps USB 3.0 signalling, backward compatible with slower USB modes.
- Card performance
- UHS-I-class SD performance up to about 104MB/s is stated in official regional material; CF and MS performance depends on the card technology.
- UHS/card mode
- UHS-I workflow. A UHS-II SD card may be accepted only at the reader/card mode actually negotiated; no UHS-II speed claim is made.
- Card formats
- SD, SDHC, SDXC, MMC/RS-MMC; microSD/TF, microSDHC, microSDXC; CompactFlash Type I; compatible Memory Stick/PRO families.
- Operating systems
- Windows, macOS, Linux and ChromeOS with USB mass-storage support.
- Build
- black compact reader body, integrated USB-A cable, four labelled slots and blue status LED
- Approx. dimensions
- Approx. 68 × 55 × 15mm body; cable about 0.5m
- SKU
- 30333
- Host connector
- USB-A 3.0 male on integrated cable
- USB ceiling
- Up to 5Gbps
- Slots
- SD; microSD/TF; CF Type I; Memory Stick
- Simultaneous access
- Up to four supported cards
- SD speed class
- UHS-I; up to about 104MB/s stated
- Conservative capacity ceiling
- Up to 512GB using the official regional specification
- Cable length
- Approx. 0.5m / 19.5 inches
- CF limitation
- Type I only; not CF Type II
1 × UGREEN 30333 4-in-1 USB 3.0 card reader
Memory cards, phone, tablet, computer, camera, charger, external drive and other illustrated accessories are not included unless explicitly named above or in the selected offer.
Questions buyers ask.
What exactly is UGREEN 30333?
a desktop-friendly USB-A 3.0 reader with four separate card-family slots.
Which host connection does it need?
integrated USB-A 3.0 cable, approximately 0.5m / 19.5 inches.
Which card slots or ports are provided?
1 × SD; 1 × microSD/TF; 1 × CompactFlash Type I; 1 × Memory Stick.
Can it access more than one card at a time?
The UGREEN gallery and regional product copy support reading and writing all four installed cards at the same time. Total bandwidth is shared.
Is 5Gbps the actual card speed?
No. Up to 5Gbps USB 3.0 signalling, backward compatible with slower USB modes. UHS-I-class SD performance up to about 104MB/s is stated in official regional material; CF and MS performance depends on the card technology.
Does it support UHS-II speed?
UHS-I workflow. A UHS-II SD card may be accepted only at the reader/card mode actually negotiated; no UHS-II speed claim is made.
What card formats and capacities can I use?
Will it work with a phone or tablet?
Direct phone/tablet use is not the intended path. A separate powered/OTG adapter may still face host, file-system and power limits.
Which file system should I use?
Use a format supported by both the host and destination device. exFAT is common for large removable media; FAT32 has a 4GB single-file limit; NTFS often fails on phones/tablets.
How should I remove a card safely?
Finish every transfer, close apps using the volume, choose Eject or Unmount, wait for activity to stop, then remove the card and reader without pulling the cable.
What is included in the package?
1 × UGREEN 30333 4-in-1 USB 3.0 card reader.