What do you call a group of hats?

They're done, all done. I removed some Wool-Ease from my stash that I was tired of having. Nothing wrong with Wool-Ease when it's used for its intended purpose. But I was tired of having this in my stash as it was never going to get used. Now it is 9 hats. No idea what I'll do with the hats but likely they'll be donated to charity. Although, I decided to keep one of the green ones and my Mom liked the solid red one so they're spoken for.