Def Leppard released a rare version of their early-era song “Glad I’m Alive,” which appears on their box set The Early Years 79-81 that comes out tomorrow.

The track was one of four recorded during sessions of their debut single “Wasted.” All four songs appear on the new box set. You can listen to “Glad I’m Alive (Early Version)” below.

The set contains remastered versions of Def Leppard’s first two albums, 1980’s On Through the Night and 1981’s High ‘N’ Dry, plus three more discs of B-sides, rarities and live recordings.

"[Def Leppard] are one of only five rock bands with two original studio albums selling over 10 million copies in the U.S.," notes a press release. "On Through the Night, the band’s debut album, was released in 1980 and immediately put the rock world on notice. … High ‘N’ Dry, the first of Def Leppard’s albums to be produced by Robert ‘Mutt’ Lange, was released in 1981. It reached No. 26 on the U.K. charts and No. 38 in the U.S., further cementing the bands status. Inside the box are a history of the albums … featuring personal insights from the band on the making and releasing of those early records as well as rare photos and memorabilia.”

Singer Joe Elliott recently noted that some of the earliest recordings, particularly the live material, presented a “warts and all” illustration of the group. "If you peel through the curtain of uncertainty that was my voice back in those days, you can hear the beginnings of a really great band," he said.

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