No, not her bulging biceps...
Watches! But not just any type of watch.
E! News can exclusively report that Diaz has agreed to a deal with upscale Swiss watch company Tag Heuer to endorse its pricey timekeeping products!
We're told the multi-million dollar deal will feature Diaz as a brand "ambassador" much like Leonardo DiCaprio has in the past. The source says the worldwide ad campaign will appear in print and will continue for multiple years.
"Cameron doesn't do many endorsements, so the company thinks she will make a big splash," explains our insider.
We're sure being smokin' hot helps, too!
—Additional reporting by Sheena Rao