If you’re one of Mario Testino's 1.1 million followers on Instagram, you already know about the famed fashion photographer’s #TowelSeries. If not, you’re missing out on a lot of hot people wearing towels—and nothing else. Mario Testino's Towel Series began when he noticed Kate Moss sat in a white robe with a towel wrapped high around her head on the set of a shoot. She became the muse for the #TowelSeries. Who is your best?