The piano, that kicks off ABBA’s disco hit ”Dancing Queen,” and is heard in so many other hits of the Swedish pop band, will be one of the star attractions at auction at Sotheby’s next month.

It may go for was much as 800,000 pounds ($1.6 million) when the gavel drops at the London auction house September 29.

The instrument comes with a certificate of authentication from the group’s co-found Benny Andersson, who describes it as ”one of a kind and a great source of inspiration.”

Sotheby’s says John Lennon’s Steinway upright piano, on which he composed ”Imagine,” sold for $1.6 million pounds in 2000.

The piano in Rick’s Cafe in the movie ”Casablanca” sold for $3.4 million last year.