Hats that were brimless went by the name Calot hat. It fit onto the back of the head with combs and bobby pins to hold it in place. It was an ideal hat to wear with freshly styled hair that a woman would not want to cover up. 

This Calot is made up of a black and white woven straw cap, from which a sheer brim flows out up to 7".

I show it one way but you can pin it on any way you want. It's in great shape! The cap is about 8" across.

This vintage hat is ready for your next vintage affair, church, USO dance, reenactors event, vintage fashion show, wedding hat, funeral hat, and great for Movie, Tv and theatre costume. Or maybe even the Kentucky Derby!
Lately, I've enjoyed movies with hats like this, such as The Guernsey and Potato Peel Pie Society” and “ Breathe”.