Kristin Cavallari to Jay Cutler, I'm a Butt Model Too!

Jay Cutler ain't the only one in his family down to show off his ass ...

Check out former NFL star's wife Kristin Cavallari -- who stripped down to some lacy black lingerie ... to promote her jewelry line?

Hey, we're not complaining!

The "Very Cavallari" reality star set up the photo shoot in Palm Springs this week while decked out in Uncommon James necklaces, earrings and rings.

No top? No problem!

Of course, her hubby Jay Cutler put his butt on display back in March 2017 during a romantic trip to Mexico.

In that pic, Jay was staring longingly at the ocean.

For Kristin's shoot -- she was gazing at the hotel pool, the desert landscape and shadows on a wall.

Again, NOT COMPLAINING!

As far as Jay's career, he's out of football and spending his free time starring in his wife's reality show ... hunting, raising their kids and watching KC run her jewelry shop in Nashville.