Amal Clooney's signature hair look leans into soft volume, touchable texture and just enough tousle to feel effortless. And while you might assume it's all about high-end styling tools, celebrity hairstylist and colorist Dimitris Giannetos recently revealed that one of the key tools he used on Clooney is surprisingly simple: the Wet Brush Frizz-Free Detangler Brush, a $15 brush that helps smooth, shape and de-frizz in one step. Giannetos told InStyle that he keeps the Wet Brush in his celebrity hairstylist kit to "reduce breakage and fights frizz.