Bringing out classroom instruments isn’t anything new for the Tonight Show. It’s always funny to see who Jimmy Fallon will welcome into the musical skit. Last night’s showing brought heavy metal band Metallica to the stage for an epic performance of their 1991 hit “Enter Sandman.” James Hetfield on lead vocals, also sporting a small horn, Lars Ulrich making use of a tiny bongo drum, Jimmy Fallon and the entire Roots crew squeezed themselves into the Music Room – sporting Metallica, Tonight Show, and Roots t-shirts for the acoustic jam.Watch the classroom instrument performance of “Enter Sandman” below:Last night’s episode came after some surprising news from Napster, announcing that Metallica’s new album Hardwired…To Self-Destruct will become available on the streaming service later this week. Previous relationships between Metallica and Napster stirred a landmark case for the music industry, when a song by Metallica was illegally downloaded and saw radio time ahead of its official release. The case was ugly, but has evidently been settled on better terms. Read more here.Metallica’s new album, Hardwired…To Self-Destruct, is being rolled via various platforms this week, with the official release set for this Friday, November 18th.