The album, like its predecessor, largely featured R&B covers; however, it does contain three compositions from the still-developing Mick Jagger/Keith Richards songwriting team, as well as two group compositions under the pseudonym of "Nanker Phelge". 12 X 5 is notable for featuring the first, and less-often-heard, of the Stones' two versions of Jerry Ragovoy's "Time Is on My Side", with a prominent electronic organ part instead of the better-known version's electric guitar. After a series of sessions in Chicago in June 1964, The Rolling Stones' UK label Decca Records released the five-song EP Five by Five. Because EPs were never a lucrative format in the US, London Records—their American distributor at the time—spread the EP songs across an entire album, adding seven new recordings to create a release of 12 songs by five musicians, hence the album's title. The rest of the songs were singles "It's All Over Now" and "Time Is on My Side" with their B-sides, plus three songs that were later included on The Rolling Stones No. 2 album. Decca would use the same cover (minus the lettering) for The Rolling Stones' second UK album The Rolling Stones No. 2 in early 1965.