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Everyone has that one product that they just can’t imagine making it through their day without. We asked a few of our favorite stars what their star product was — and of course, we had to find out how you could buy it for yourself! Make sure to check out the September issue of StyleWatch to find out what products Hilary Duff, Tyra Banks, and other celebs can’t live without too.

“I’m just obsessed with my Yves ...