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Proving that two divas are better than one, Britney Spears lent her voice to the new remix of Rihanna’s hit “S&M.” Rihanna teased fans with some build up on Twitter earlier in the day, hinting at a "sexy collabo'," before premiering the "RIHmix" on New York radio station Z100 on Monday. The already scandalous song gets a sexy lift from Spears on the second verse, as she sings, "Just one night full of sin/ Feel the pain on your skin/ Tough, I don't scream 'mercy'/ It's your turn to hurt me/ If I'm bad, tie me down/ Shut me up, gag and bound me/ 'Cuz the pain is my pleasure/ Nothing comes better."

Getting Spears involved was a surprise to Rihanna herself. "It's very strange. Britney never does features. It was really amazing that she really wanted to be part of this song," Rihanna said. While the remix is a collaboration of epic diva proportions, the 23-year-old revealed that the idea of working with Spears came directly from her fans. "In order to do a remix, it had to be major," she said. "I asked my fans last week who they wanted me to collaborate with, and Britney was one of the most popular names." The song will eventually be available for download on iTunes, but for now you can check it out on Z100's website. –EMILY EXTON