@fBoyle-- I wouldn't recommend the plastic rubber flash drive wristbands. I had one and I lost it after three days. It must have slipped off while I was working. I didn't even notice and I never found it.
If you want a flash drive wristband that's comfortable, durable and high quality, get ready to pay twice as much as a regular flash drive. The best USB flash drives in the shape of a wristband on the market are the leather ones. They are more durable than the rubber ones and if it comes with a clasp, it's unlikely to fall off.
But even with these I've read customer reviews that said the pieces fell off or it was just too bulky and uncomfortable.
I've yet to encounter a flash drive wristband that I would be completely satisfied with. If anyone has, I would love to know about it as well.