NEW YORK, NY.- A recently discovered guitar that John Lennon used to record multiple Beatles songs in the 1960s before it went missing for 50 years has sold at auction for $2.9 million, becoming one of the most valuable pieces of memorabilia from the band.

The 12-string acoustic guitar, called the Hootenanny, was believed to be lost after Lennon and his bandmate George Harrison used it to record the 1965 Beatles albums “Help!” and “Rubber Soul,” said Julien’s Auctions, the Los Angeles-based auction house that handled the sale Wednesday.

Later that year, Lennon gave the 1964 guitar, made by German instrument manufacturer Framus, to Gordon Waller of the British pop duo Peter & Gordon. Waller passed it on to one of his road managers, who took the guitar to his home in the British countryside and tossed it in the attic, the auction house said.

More than 50 years later, a man in Britain discovered the guitar in his parents’ attic as they were moving out of the house, Darren Julien, a co-founder of Julien Auctions, said in a video. After they found it — along with its original guitar case — they alerted the auction house in March, Julien said.

“The son told us that he had always heard his dad talk about this guitar, but he’d believed that it was lost,” Martin Nolan, another co-founder of Julien’s Auctions, said in the video.

The auction house consulted with Andy Babiuk, a Beatles expert who has authenticated the band’s memorabilia in the past, to verify the guitar. After comparing the instrument’s wood grain and the wear patterns to those in archival images, Babiuk determined that the guitar was the one played by Lennon, the auction house said.

“Check your attic, folks,” Nolan said.

Other famous instruments have turned up after being lost for more than five decades. Paul McCartney’s Höfner violin bass was found last year. Lennon’s Gibson acoustic guitar, which had also been forgotten, was sold for $2.4 million to an anonymous buyer in 2015.

After half a century in the attic, Lennon’s Hootenanny was in need of some restoration. Ryan Schuermann, a repairperson in LA, conducted a complicated process involving removing its neck and attaching it back to the body at a better angle.

The guitar, which features a spruce top, mahogany back and sides, a 19-fret rosewood fingerboard and a decorative sound hole rosette, was sold along with a Maton guitar case and a DVD boxed set for the movie “Help!” and a collection of photographs from the set of the film.

The value of the guitar was estimated at $600,000 to $800,000 before the auction. It was sold to an anonymous buyer for $2,857,500, becoming the fifth-most expensive guitar ever sold, the auction house said.

“Finding this remarkable instrument is like finding a lost Rembrandt or Picasso,” Julien added in a statement, “and it still looks and plays like a dream.”

This article originally appeared in The New York Times.