Olivia Culpo is baring it all in order to drum up interest in her upcoming clothing line ... rockin' nothing but a tiny bikini bottom in a steamy new ad.
Christian McCaffrey's fiancée posted the short commercial on her Instagram page Friday morning ... and, yeah, it's spicy, to say the least.
You can see the former Miss Universe champion sitting by a pool with her top off ... posing for a camera placed strategically behind her.
In a subsequent IG post, Culpo explained it was all to help sell her Montce x Culpo '24 Collection -- which officially drops on March 25.
This ain't the first sexy advert Culpo has taken part in this week ... on Tuesday, she and McCaffrey posed for some sweaty shots to help hawk Bodyarmor's new zero-sugar drink.
It could be one of the last times, however, that Culpo films as an unmarried woman.
The 31-year-old is slated to tie the knot with McCaffrey in just a few months -- revealing in an interview last week that the ceremony is slated to go down in "early summer."