What's something unique that you carry on you every day?

Same here, I got this from being in the military, where you were issued a pair when you arrived in the ship.

I keep a pack of disposable ones in my fanny pack. It's useful because sometimes someone in the group needs em.

I keep a pair of those loop ones in my backpack for the same reason

One pair in my travel stuff always. Habit from grad school when I lived next door to a frat house