A really good sleep mask

I can’t sleep in a plane/train/car, but I use this anyway to “rest” and avoid watching half of a movie with no sound over a stranger’s shoulder. Bonus points if you need to take a daytime nap to catch up with the time change at your destination.

It doesn’t have to be this one, because this one is stupidly expensive, but it has eye cups that allow you to blink in the darkness and a strap that doesn’t make my ears hurt.