Nice card reader for pro users, but not right for everyone.

When you work with Apple computers, you have to make sure that you have the proper accessories to connect to all of your devices. That may sound strange, but it’s the battle I’ve been fighting for the past couple of years since I upgraded to the newest MacBook Pros that only feature USB-C/Thunderbolt 3 ports. I’m loyal to Apple and don’t get me wrong — as a creative professional, I feel it’s the best tool to get my jobs done. The only complaint I have is that Apple designers removed the pro-level ports from the powerhouse machine that is the MacBook Pro. Because of that, I have to supplement my mobile set-up with attached docks like this 4-Slot Pro Card Reader from XCELLON. 



The CR-CFASD 4-Slot Pro Card Reader provides users with an option to simultaneously exchange images, movies, and other large files between the cards that are connected in the dock. The device is bus-powered and doesn’t require any special software to get started. It’s a ‘no-fuss setup.’ The card reader offers users two (2) CFast and two (2) SD card slots. This makes it possible for users to work off of multiple cards quickly and efficiently. The CR-CFASD takes advantage of the USB 3.1 Gen 2 10 GB/s bandwidth. It provides up to 800 MB/s transfer time. The maximum speed is split between all four slots. So if you use 2 CFast card slots, the potential maximum transfer speed would be 400 MB/s per slot. The card will simultaneously read and write to the cards. Finally, the dock features aluminum housing to keep it cool. 


  • Ports: 
    • 2 × CFast 2.0
    • 2 × SD UHS-II
  • Transfer Speeds
    • Max: 800 MB/s
    • SD UHS-II: Up to 270 MB/s
    • CFast 2.0: Up to 550 MB/s
  • Computer Interface: USB Standard-A or USB Type-C (Thunderbolt 3 port compatible)Power
    • Self powered: 12 V/ 2 A (24 W) adapter
    • Bus power: Full 4-slot operation requires 3 A source
      • Limited to 2-slot operation from less than 3 A source
  • Cables: USB 3.1 Gen 2: Type-C to Standard-A
  • Cable Length: 19.7 in. (50 cm)
  • System Requirements:
    • macOS 10.6.x or later
    • Windows 7 or later
  • Dimensions: (H × W × D)1.1 × 5.8 × 3.3 in. (28 × 147 × 85 mm)
  • Weight: 10.4 oz. (294.8 g)


The first thing I noticed with this card reader was its size. It comes in a fairly large box. To be fair, the reader comes with two cables and a power supply. That said, the device itself is fairly large. Perhaps it’s to accommodate the larger format CFast cards, but I actually reviewed a similar card reader from XCellon a few months ago that was compact in size and it included a slot for a CF card. That being said, I just felt like this card reader was a bit large for what it does since I’ve seen much smaller card readers that include more slots.


Second, the card reader ships with a small user manual and a note that says, “The card reader will heat up during general operation. This does not indicate a malfunction, and it is normal and safe. Keep the device free from obstructions on all sides and with plenty of airflow.” I’ve tested a lot of card readers and docks and I can say that most of them heat up while in use — especially if there is PD available. That said, I did detect a substantial amount of heat after just a few minutes of use. So, I used an infrared thermometer to take a temperature reading. It fluctuated between 109-115 degrees. Typically anything below 140 degrees is ‘safe’ for use and not in danger of overheating or damaging the connected accessories. However, I thought that the fact that there was a warning card enclosed meant that Xcellon had experienced this phenomenon many times.


As far as operation goes, the card reader does its job pretty well. I did a speed test using an SD card. The card I chose was rated with a data transfer speed of 30MB/s. According to the specs of the card reader, it should have had no issue delivering that type of data transfer speed. I ran a Blackmagic Disk Speed Test on the card using the card reader as the conduit for the test. I was getting 8.9 MB/s write and 45.2 MB/s read. I also transferred a file to the SD card from my computer. The file was 2.36GB in size and it took approximately 4 minutes and 20 seconds to transfer. That is a rate of 9.08 MB/s which is far less than the 30 MB/s the card is rated for.


I also noticed that when I removed SD cards from the card reader that there was a horrible scraping sound and the bottom of the cards got pretty marked up.


While I like the concept of this device and the ability to transfer data between connected cards, I’m not sure this is the right card reader for me. It gets a little too warm for my taste and is just a little too large for my purposes. I like my card readers to remain hidden and this one would have to live on my desktop. I’m sure that someone will find this card reader appealing, but it’s just not for me. 

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