Summer's Hottest Hats

Not just for bad hair days, the toppers Jessica Alba, Ashlee Simpson and more wear keep them looking and feeling cool

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RACHEL ZOE

Why we love it: Because no boho ensemble is complete without this floppy '70s staple
Where we'd wear it: In the spirit it was meant to be worn – with a maxi skirt and giant sunglasses, while dancing on the grass at an outdoor concert