Led Zeppelin will release a limited-edition 7" yellow vinyl single featuring previously unreleased mixes of "Rock and Roll" and "Friends" for this year's Record Store Day. This is the first time the band has put out an exclusive for Record Store Day, which takes place on April 21.

According to a press release, this mix of "Rock and Roll" stems from the "Sunset Sound Mixes" made for Led Zeppelin IV, of which only two tracks have been heard before: the original version of "When the Levee Breaks" and "Stairway to Heaven," which appeared as a special mix on the 2014 Deluxe Edition of Led Zeppelin IV. The "Olympic Sound Mix" of "Friends" removes the orchestration, "offering a true fly-on-the-wall feel from the band’s recording sessions for Led Zeppelin III at Headley Grange," according to the release. Jimmy Page produced both recordings.

This single represents a flurry of activity for Led Zeppelin, who are recognizing their 50th anniversary this year. March 23 will see a reissue of their 2003 live album How the West Was Won, and Page has promised another release from their concert archives. In October, they'll put out Led Zeppelin by Led Zeppelin, a 368-page hardcover book that lists the three surviving members as authors. It features many unseen photographs of the band and is described as "the first and only official illustrated book to be produced in collaboration with the members of the band.”

Record Store Day is a global celebration of independent record shops that has been held every year since 2008, with artists offering limited-edition releases sold exclusively in select stores. This year, the hip-hop group Run the Jewels have been named as the day's ambassadors.