The essential kit bag has two levels of essential. There's the essential that you need to use day in, day out - like chargers - and there's the essential that you might only use now and again, but when you need it you REALLY need it, so it has to be in the bag.
One such item for me is the USB stick. I want to have it in there, but it'll just get used now and again. USB sticks can be kind of boring, no doubt you've been given lots of them as freebies... But I think there's good reason for being a bit more discerning than using one of those!
What do I want from a USB stick? I want it to be as small as possible with a decent amount of storage, fast transfer, well made and having been burned in the past, ideally from a reputable brand.
Why this specific model? Well it fits all of the above criteria with the added bonus of USB C support, so I can even plug it into my phone (as well as my XPS' USB C port!).
I've used it for all sorts of things, aside from the obvious shuttling data around it's powered Linux installs, Windows Anniversary Edition updates, content transfers from phones even. Basically... A worthy kit bag essential.
Also worthy of note, I previously packed a Leef Bridge, offering very similar functionality but with microUSB rather than USB C.