The 'My Songs Know What You Did In The Dark' band worked with the Hole singer on 'Rat a Tat' for their new album, 'Save Rock and Roll', and said she completely understood what they were trying to achieve with the song.
Frontman Patrick Stump told website Digital Spy: ''[She] really got exactly what we were going for. To the point where there are lyrics on the song we did with Courtney where I don't know what she wrote and what I wrote.
''She was so in tune with us that some of her lyrics sound like ours and some of ours sound like hers. That's what you hope for in a collaboration that you're in sync with each other.''
The band - which also includes Pete Wentz, Joe Trohman
and Andy Hurley - are also one of the few artists to support acts who have risen to fame from TV singing shows such as 'The X Factor'.
Patrick added: ''I think yeah, there are ways that some people that can be manufactured but there are absolutely ways to get beyond it, Kelly Clarkson has spelled out who she is as an artist, and you forget Carrie Underwood is from that, people can outlive it and overcome it.''
'Save Rock and Roll' is out now.
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