My scalp and some hair. :P

I'm not a really big hat wearer, but in winter it is a simple wool watchcap.

In summer, my favorite for the woods is a dark brown digger hat. I have a three strand braid of paracord for a band, and the left side is up. I usually tuck a small bit of 2" wide, bright orange ribbon cut from a piece of cotton fabric I got for this purpose years ago. I can wind it mummy style for my lower face, or take off a bit with my knife for tinder or blazing a trail.