Quaternary is an EP by the heavy metal band Mötley Crüe. It was released in 1994 on Elektra.[3] The EP, which was initially going to be titled Leftovers, was made available as a mail-in offer for purchasers of the self-titled album in a limited quantity of 20,000 copies.
The EP features one song from each member of the band ("Planet Boom" by Tommy Lee, "Bittersuite" by Mick Mars, "Father" by Nikki Sixx, and "Friends" by John Corabi), along with the song "Babykills" which is performed by the entire band.[4]
The rap metal-influenced "Planet Boom" was later released on the soundtrack for Tommy Lee's then-wife Pamela Anderson's movie Barb Wire. However, the song was remade, credited to Tommy Lee only, and the title was changed to "Welcome to Planet Boom". A music video was also released for the song around the same time as the film's release.