Lady Gaga and Tony Bennett dazzle in H&M's glittery, festive 2014 holiday commercial. As silver and gold confetti falls all around them, the veteran performers belt out the jazzy number with holiday cheer. What's the song?

It's 'It Don't Mean a Thing (If It Ain't Got That Swing),' Lady Gaga and Tony Bennett's cover of Duke Ellington's 1932 jazz hit. Gaga and Bennett's version appears on their 2014 jazz album, 'Cheek to Cheek,' which was just recently nominated for a Grammy -- so you know it's good. In addition to 'It Don't Mean a Thing,' 'Cheek to Cheek' is filled with the pair's covers of traditional tunes like Cole Porter's 'Anything Goes' and the album's titular track, Irving Berlin's 'Cheek to Cheek.'

Hear the song in the H&M commercial above, and check out the full version of Lady Gaga and Tony Bennett's 'It Don't Mean a Thing' in the video below!

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