Having already released expanded reissues of Kill 'Em All, Ride the Lightning and Master of Puppets in the past few years, Metallica are moving on to their fourth album. Yesterday, they tweeted out a video that suggests that a box set for 1988's ...And Justice for All is on the way.

The 33-second clip below shows various stages at the assembly plant, with vinyl discs being cut, CDs put into sleeves, numerous pieces of memorabilia, a box being shrink-wrapped and, finally, a completed box coming off the assembly line and placed in a stack with others. The caption consisted of the caption, "#comingsoon."

While details have yet to be unveiled, their box for Master of Puppets, which came out last November, could provide some clues as to its contents. In addition to the remastered original on CD and vinyl, it contained two discs of interviews, three CDs of rough mixes, riffs, demos and outtakes, eight full concerts (four on CD, two on DVD one on vinyl and another on cassette), a 108-page hardcover book and various memorabilia.

Metallica are also preparing to launch their own line of whiskey, called Blackened. Earlier this week it was learned that their music has a role in the aging process. "After the whiskeys have been combined in the black brandy casks for finishing," their website said, "they’re jolted back to life by the unmistakable, earth-shattering music of Metallica. Using our proprietary sonic enhancement system BLACK NOISE™, the whiskey is pummeled by sound, causing it to seep deeper into the barrel, where it picks up additional wood flavor characteristics."