Review: Dual-Slot SDXC/microSDXC Mobile Card Reader, CFexpress Type B 165GB Cobalt Memory Card

ProGrade introduces a dual-slot USB-C SDXC/microSDXC UHS-II mobile card reader optimized for mobile use and a CFexpress Cobalt cards of 165GB that is capable of 1700MB/S transfer speeds.

The USB-C card reader is tiny. It is a quarter of the size of the regular size ProGrade USB-C dual microSDXC card reader which I thought was small. Except for the size, what makes it mobile is that it has the USB-C connector built-in. That combination makes it an ideal companion for USB-C capable smartphones and tablets — as well as your desktop PC.

Not only can you offload images and footage from increasingly powerful mobile devices with it, you can also use it as a flexible storage extension. The one thing that would worry me, though, is losing both reader and card. Perhaps ProGrade should offer a small carry box for the reader or provide for a keyring hole so that you can’t lose it when you’re using it as a dock for a memory card that’s semi-permanently attached to your smartphone or tablet.

The performance of the reader is the same as that of its larger sibling, but it supports both SDXC and microSDXC cards instead of two microSDXC cards. Top and bottom look the same and have a tiny LED, which might leave you guessing at how to insert your card, but is actually easy: switch the reader with the card slot you need to the top and you’ve found the right way to insert the card.

ProGrade Digital’s CFexpress 2.0 Cobalt Memory Card now comes in a somewhat cheaper 165GB and 325GB size. It is now rated for read speeds of up to 1700 MB/s (previously 1600MB/s) and write speeds of up to 1500 MB/s (previously 1400MB/s), due to the card’s support for the NVMe PCIe 3.0 x2 Bus. The Cobalts’s minimum write speed won’t drop below 1400 MB/s, the company says, but on my mid-2017 iMac it never surpassed the 1200MB/s mark when using ProGrade’s own PG04 Thunderbolt 3 reader. That’s still a very respectable speed and it wouldn’t surprise me if you would get the advertised maximum on an M1 Mac, for example.

Pricing of these and other ProGrade products is available on the ProGrade online store, with the 165GB card a sensible offering for photographers and less expensive than ProGrade’s larger cards.