The Beach Boys' Brian Wilson (right), who jokes with Lennon

"The recording is an extraordinary conference call, a simultaneous telephone interview of all four Beatles, plus Brian Wilson of the Beach Boys, and surfing music guitarist Dick Dale," said Dave Gioia of Collectors Universe.

The recording includes comments by Beatles John Lennon, Paul McCartney, George Harrison and Ringo Starr, along with Wilson and Dale.

There also are brief excerpts from the Beatles hit, Can't Buy Me Love and the Beach Boys' classic Fun, Fun, Fun and Dale's instrumental, Mr Eliminator.

Unique

On the recording, the Beatles talk a range of topics from their clothing and hair styles to an untitled movie project that eventually became the acclaimed, A Hard Day's Night.

Mr Gioa explained the origins of the recording, saying: "The recording was made on 11 March 1964 at the height of Beatlemania to promote a Hollywood event called the Teen Fair.

The Beatles have become the most collectable group of all

"It was pressed on an eight-inch 33 rpm Capitol Records acetate disk with a typewritten label."

A music fan spotted the 33 rpm record with its type-written label in a box at a well-known flea market in Newport Beach and paid $5 for it.

"Earlier this year, a record collector purchased it for only $5 at a Los Angeles area flea market, and he consigned it to the auction," Mr Gioa said.

"Obviously, it was worth a lot more than five bucks. It apparently is the only copy in existence."