Own a piece of Britney Spears.

On October 29, the singer, 25, wore a sexy pirate Halloween costume to a West Hollywood bar. In a typical Spears move, as reported by Us, she swapped outfits (and bra!) with waitress Nicole Calvin midway through the night in the club bathroom stall.

After striking up a conversation with Calvin, 25, Spears asked her if she wanted to trade her slinky halter top and jean skirt for Spears’ own pirate costume. (This isn't Spears' first scandalous fashion move.)

“It was random,” Calvin tells Us Weekly in its new issue, on newsstands now. “Britney laughed the whole time and commented about how perky my boobs were and that she wished she’d had hers done."

After the swap — the latest in Spears' downward style spiral — "her assistant said, ‘We’ll get your stuff back to you,’" Calvin says. "But no one ever called me.”

Now Calvin has partnered with Usmagazine.com to auction off the costume on eBay to benefit the Make A Wish Foundation. Bid here.

"I want to help people, especially since the holidays are coming up," Calvin tells Usmagazine.com.

ARE U SERIOUS??

SOURCE: USWEEKLY.COM