Miley Cyrus might just be the biggest Billy Idol fan out there.

The 23-year-old singer joined Idol on stage for a special performance of "Rebel Yell" at the iHeartRadio Music Festival on Friday, and while fans were surprised by her appearance, it's her ensemble we can't get enough of.

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"Singing with me Miley Cyrus! Let's hear it!" Idol announced to the crowd as he brought out Cyrus for their duet.

"Singing with Billy f**king Idol, let's do it!" she yelled back to a cheering audience.

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Cyrus then debuted her full get-up, which included a Billy Idol leather jacket:

A Billy Idol vintage tee:

Billy Idol pants:

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And Billy Idol sunglasses:

See their performance below:

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While Cyrus is totally in her element onstage, she recently vowed never to do another red carpet.

"[A year ago] I had to do the [A Very Murray Christmas] premiere, and I will never do a red carpet again," she told Elle. "Why, when people are starving, am I on a carpet that's red? Because I'm 'important'? Because I'm 'famous'?"

"That's not how I roll," Cyrus further explained. "It's like a skit -- it's like Zoolander."