Sony has had a torrid history with proprietary memory formats, and this is the next version of that. We hate it. You hate it. But up until recently, there was no other manufacturer of these cards, so we had to play their games and pay their prices.

All of that being said, the memory card you're getting here is very, very good. It's incredibly fast (700 MB/s write, 800 MB/S read), and as part of their "Tough" series, it is also dust, moisture, and shock resistant.

So if you need this memory type for high-speed shooting on Sony's latest cameras like the FX6, FX3, and A7s III, then this card is a reliable, speedy way to get it done.