My son does not really like to wear hats.  He kept this one on the entire time at the beach (2 hours).  He's 3.

The adjustable band is fantastic for snugly fitting it to his forehead.  The chin strap was a nice feature & since he loves Max & Ruby and the episode where Max wears a rain hat with a chin strap, he was open to having it fitted under his chin.  I can see how other children might not like this so much - but the band will keep it on in a stiff breeze.

The vented top was great - his head didn't get nearly as sweaty as I would have expected.

The brim covered his entire face & the back covered all of the back of his neck & upper shoulders from the sun.

It's very light weight, the darker underside definitely helped with reducing reflected light.

5 day cruise & my fair fair fair son hardly looks like he's been in the sun at all. :)