Last week, Metallica dropped Hardwired, a breakneck three minutes chock-full of palm-muted machine-gun riffery - and it turns out Kirk Hammett's guitar solo was played on Peter Green's legendary 1959 Les Paul, judging from a new in-the-studio clip.
At 6:44 in the video above, Kirk can be seen tracking the solo on 'Greeny' itself - we're not sure whether he used it on the final take, but it's concrete proof that the wah-happy guitarist used it on the album.
Elsewhere, the video depicts the writing and recording of the new Metallica single - expect more of these in the run-up to the release of Hardwired… To Self-Destruct in November.
Back in May, Kirk gave us an in-depth interview on how Jimmy Page encouraged him to buy Greeny, and his plans for the fabled guitar.
"I'm not a guy who'll buy a guitar just to stare at it and covet it; that is the death of a vintage guitar," Hammett states.
"Guitars are built to be played. The more they're played, the better they sound. The more they're played, the more reactive they are.
"I bought Greeny and, literally, by the next show she was up on stage in front of 40 to 50,000 people, being sweat on all over by me.
"I'm on my way to the studio right now. I texted my tech and said, 'Have Greeny in tune, we're using her today,' and I'm going to try and use all of the three main sounds that are in her."
Hardwired… To Self-Destruct is out on 18 November via Blackened Recordings. Watch the full Hardwired video below.