Metallica members James Hetfield, Lars Ulrich, and Kirk Hammett, Guns N' Roses' Slash, Duff and Axl, and Skid Row vocalist Sebastian Bach. Even better, uploaders RUM Entertainment YouTube called the jam a "shambolic stumble", which is… accurate.
The video shows everybody in 1990 for the R.I.P magazine birthday party, at the Hollywood Palladium in Los Angeles. Can you just imagine the amount of insanity happening backstage or in the crowd during this gig?