Other World Computing’s OWC Envoy Pro EX with USB-C is one of the slickest and sleekest solid state drive solutions around and a fine accessory for Macs with limited storage capacity. In other words, just about all of ‘em.
Designed for high performance storage and/or backup, it's palm-sized and only .33 pounds, which means it’s small enough to fit into a coat pocket, backpack, or briefcase. It comes with a USB-C cable, which you would expect it to — but these days, you can’t be sure that companies will include the cables you need.
Compatible with macOS 10.12 and higher (as well as Windows), it’s bus-powered, so you need no external, bulky power supply. The OWC Envoy Pro EX with USB-C is housed in anodized aluminum housing that’s dustproof with an IP67 waterproof rating that's certified to survive 30 minutes in one meter of water (not that you should ever submerge a drive in any sort of liquid!). Plus, according to the folks at OWC, it works just fine in temperatures from freezing to 104 degrees Fahrenheit. And it’s guaranteed by a three-year warranty.
Inside the shell is a NVMe M.2 SSD that delivers speeds up to 980MB/second (which makes it, as best as I can tell, the fastest external USB-C SSD available) and, of course, Thunderbolt 3 compatibility. You should note that there’s no security slot, though the size of the drive makes it simple to stow safely away.
The OWC Envoy Pro EX with USB-C comes in capacities of 250GB, 500GB, 1TB, and 2TB for, respectively, $129.99, $179.99, $249.99, and $429.99.
Apple World Today Rating (out of 5 stars): ★★★★★