Jennifer Aniston Lounges in Underwear for Sexy New Ad

Credit: Courtesy of Smartwater (2)

Leave 'em thirsty for more, Jennifer Aniston!

In striking, black-and-white new ads for Glaceau smartwater, the actress, 42, shows off her perma-toned bod in two revealing new photos.

In one shot (with the tagline "smart because taste never goes out of fashion") Aniston emerges from the backseat of a limo clad in a tight little black dress. In another, she flashes her gams even more in a pair of ladies-style "tightey-whiteys" and a loose-fitting shirt and she lounges. ("Smart because life is best distilled," reads the tagline in the second pic.)

Yoga and fitness buff Aniston has been a spokeswoman for Glaceau SmartWater since 2007. Soon after the star signed on, a SmartWater executive said, "Jennifer truly embodies what smartwater is all about as she combines substance and style."