Rather than running around town shopping for last-minute presents, Heidi Klum is in total relaxation mode before the holidays.

The model, 39, shared a very revealing photo of herself on Twitter Tuesday, Dec. 18 from a tropical getaway.

PHOTOS: Heidi Klum's amazing body transformation

"Island speed," she captioned the shot, which showed her lying on her stomach, tanning topless in only black bikini bottoms.

The picture shows off the Project Runway host's toned body -- and a lot of sideboob! In the background of the picture is a stunning beach, ocean and tropical island. Though Klum doesn't say the location of her getaway, the model was tweeting last week from Dubai.

PHOTOS: Heidi Klum's life as a single mom

Back in October, the mother of four told reporters she planned on celebrating Christmas with her children, Leni, 8, Henry, 7, Johan, 6, and Lou, 3.

"We're going to get a big Christmas tree and we might go to Disneyland. We go all over the place," Klum explained. "My children are everything for me. I've always wanted to have a big family. And I'm fortunate enough to have four."

PHOTOS: Heidi Klum and Seal -- the way they were

It's the first holiday season in seven years that Klum is not spending with Seal; the spouses announced their split in January of this year.

This article originally appeared on Usmagazine.com: Heidi Klum Sunbathes Topless, Flashes Sideboob on Tropical Vacation: Picture