Black Beard's Hat is treasure that can be obtained in Sly Cooper: Age of Thieves in the episode Coopers of the Caribbean. It is worth 245 coins and the time needed to reach the safehouse is thirty-seven seconds.
"The mysterious Black Beard has a collection of hats that he wears, but this one stands out above the rest. This seems to be too modern for it to be from this time period, but the materials it's made out of makes it valuable nonetheless. And why is Penelope's logo on it? Well, all things considered, it's fairly obvious she knows that this hat just wasn't worth wearing. It does look valuable, after all..."
It is located underneath a large broken ship piece that must be destroyed with a Sticky Bomb. Needless to say, only Bentley can obtain this treasure.