Britney Spears Shares Racy Upside-Down Throwback Snap

Britney Spears Shares Sexy Upside-Down Throwback Pic with a Funn…

Rebel Wilson Plays Justin Hartley’s Hype Woman at 'Senior Year’ …

Rebel Wilson Reveals She Had to Get Britney Spears' Permission f…

Megan Fox Reveals She Cut a Hole in Her Jumpsuit For Sexy Time W…

Hilary Duff Calls Posing Nude a Combination of Terrifying and Fr…

Tim McGraw & Faith Hill on Helen Mirren and Harrison Ford Joinin…

Watch Angelyne in Rare Interviews About Her Iconic L.A. Billboar…

David Oyelowo on Joining the 'Yellowstone' Universe With Bass Re…

Johnny Depp Not Dating His Attorney Camille Vasquez (Source)

Kourtney Kardashian's Kids Cringe Over Her PDA With Travis Barker

Prince William and Kate Middleton Go Hollywood Glam at ‘Top Gun:…

Ryan Reynolds Recalls 'Beautiful' Moment With His Brothers Prote…

Adam Demos on 'Sex/Life' Season 2 and His Girlfriend's Reaction …

Travis Barker and Kourtney Kardashian Arrive in Italy for Offici…

Zendaya and Tom Holland Show PDA in Boston

Ashley Graham Shows Off 'New Tummy' Months After Giving Birth

Megan Fox Details 'Blood-Drinking Ceremonies' With Machine Gun K…

Lil Jon on Why He Started Doing Home Renovations With New HGTV S…

Randy Jackson Reveals Which Celebs He’d Like to See on ‘Name Tha…
It's Britney Spears circa 2003, b**ch.
The "Slumber Party" singer posted a sexy throwback photo on a Sunday, as opposed to a Throwback Thursday or Flashback Friday. (Hey, we don't mind.)
RELATED: Britney Spears Has a Racy 'Slumber Party' in Sexy New Music Video With Tinashe
Spears took to Instagram to share a glimpse at her In The Zone-era body -- a throwback shot from that epic topless Mark Rolston photo shoot for the October 2, 2003 issue of Rolling Stone. You know the one.
"My friends sent me this picture today… and it's weird because I just realized it's one of the only pictures I've ever taken upside down!" the 34-year-old captioned the revealing snap.
The racy photo from the same era that brought us "Toxic" isn't such a far cry from Spears' current physique, as she recently told Ryan Seacrest that she is the fittest she's been in "probably 20 years."
RELATED: Britney Spears Reveals the Perks of Photoshop: 'I Might as Well Eat Six Pieces of Pizza'
That would explain why Spears has taken to sharing more scantily clad shots in recent months, along with releasing the sultry music videos for "Slumber Party" and "Make Me."
MORE: Britney Spears Makes Out With Shirtless Hunk in Steamy 'Make Me' Music Video
When you're a smokin' mother of two with abs like that on the week of your 35th birthday (B's birthday is December 2nd!), we say it's allowed. For even more Britney, watch the clip below.