John Lennon's "lost" 1962 J-160E Gibson acoustic guitar is to star in a November 6-7 sale at Julien's Auctions in Los Angeles.
The guitar, which is valued at $600,000-800,000, is a hugely important piece of Beatles history.
Lennon used it to compose some of the band's most iconic songs and it can be heard on both Please Please Me and With the Beatles.
It went missing after a 1963 concert and has only recently resurfaced, 50 years on. It was discovered by a man named John McCaw, who reportedly found it in a second hand shop.
McCaw contacted Andy Babiuk, an expert on Beatles instruments, who explained: "I get calls and email all the time with people telling me that they think they have an instrument owned by The Beatles and 99% of the time it's nothing, but there was something about McCaw's story that was intriguing…
"Wood grain is like a fingerprint, no two are the same, and without a doubt it is a match.
"It is one of the most important of all Lennon's Beatles guitars, as he used this J-160E to write some of The Beatles' biggest hits, and played the guitar on countless live performances and on many Beatle recordings.
"It is without a doubt one of the most historically important guitars to ever come up for auction."
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