Supermodel Bar Refaeli – one of the most indemand bikini models – posted a topless photo of herself on her Twitter account on Monday. Leonardo DiCaprio’s former girlfriend had last posted a candid snap of herself during a painfullooking dental examination.

The photograph features the former Sports Illustrated model topless, while submerged in water, with the caption, “Watch your back!” In the black and white image, Rafaeli can be seen from behind wearing nothing but a checkered string bikini bottom – with visible tan lines – as she coyly holds her triangle top, the Daily Mail reported.

She also posted a mysterious picture of herself with five small children, and wrote: “Can u think of a better day to start the day?”