Watch Bruno Mars Sing Elvis, Talk Spanx on 'Carpool Karaoke'

Between singing hits, pop star revealed what's in his tour rider and why he's always wearing hats

Bruno Mars sang his own hits and Elvis' "Jailhouse Rock" as he helped James Corden wade through traffic for "Carpool Karaoke."

Bruno Mars helped James Corden get to work last night in the Late Late Show host's "Carpool Karaoke." The duo sang a over a dozen Mars songs – "24K Magic," "Locked Out of Heaven," "Grenade," "Versace on the Floor," "If I Knew," "Uptown Funk" and "Perm" – and talked tour riders, Elvis Presley and Mars' casual 24K Magic attire.

"If I was wearing that level of silk, I would think I would be happy as well. If I could dress like that all day, every day, I'd be over the moon," Corden said. "It's a very breathable fabric." Mars revealed that he's always wearing caps because his curly hair is unmanageable, which inspired Corden to test a theory that Mars can rock any hat, even a gold-sequined one.

In his childhood, Mars said he impersonated Elvis Presley in a 1950s revue, sparking an impromptu rendition of "Jailhouse Rock." Later, while singing "Versace on the Floor," Corden notes that the lyric "I unzip the back to watch it fall" leaves out the involvement of Spanx. The late-night host adds that he's never dated anyone who wore Versace. When Mars asks where Corden's woman shops, he says, "Target."

Watch behind the scenes footage of Bruno Mars as he puts the finishing touches on new LP '24K Magic' and continues his quest for the next "Uptown Funk.