Last night (May 29), James Hetfield took time out from finishing up Metallica's new record to hang out with some old friends. He stopped by the Fox Theatre in Oakland to jam with Corrosion of Conformity. You can watch the video above.

The song he joined them for was "Seven Days," which appeared on their 1994 album, Deliverance. Hetfield contributed guitar and background vocals. While he stayed on the far side of the stage for much of the song, he ventured towards the center during Woody Weatherman's outro guitar solo. On their Facebook page, Corrosion of Conformity called the performance a "Hetsploitation."

The association between the two bands goes back more than 20 years. Corrosion of Conformity opened for Metallica regularly from 1995-97. Hetfield sang backup on "Man or Ash," from 1996's Wiseblood, and Pepper Keenan, the lead vocalist for Corrosion of Conformity, returned the favor on Metallica's cover of Lynyrd Skynyrd's "Tuesday's Gone," from 1998's Garage Inc., which featured their hit take on Bob Seger's "Turn the Page."

Metallica will soon be getting together to complete the long-awaited follow-up to 2008's Death Magnetic. “We’re now coming towards the end of the musical creative process and we’re starting to look ahead and the process of how we’re gonna share this record with the universe,” Lars Ulrich said a couple of days ago. “The month of June is basically when we’re gonna sit down and figure what we’re gonna do with it all; what we’re gonna call it and what’s gonna be on it."

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