[He shakes his head, though the frequency with which he's getting asked that very same thing is starting to get pretty funny to him. Does 2B get asked that as often as he does? Maybe next time he sees her, he ought to ask]

Not rude at all. [It's not like she's assuming he can't see, after all] Lots of people think I'm wearing a blindfold, but these're actually goggles. Standard-issue for YoRHa androids and everything.

[Raising a hand, he taps the material over his temple with one finger, though there's no need to indicate the object of their conversation]

These actually improve vision out in the field, so they're pretty handy for any unit.