I saw this in a store and don't like to buy a hat in stores with everyone and their dog trying them on (I'll leave it at that).  So I got the description and found it here.  This hat works great and fits to your head with a pull tie in the back.  For that windy day, the tie can pull up to your neck to keep the hat on.  The underside is black so it doesn't reflect the light on your face - very helpful in the water.

I used this on a trip to French Polynesia (Tahiti) and it worked great - full sun, got wet, held on, wind, rain, you name it.