The Range Rover William and Kate used to transport their newborn son Prince George home from hospital is auctioning to raise funds for charity.
The proceeds will go towards equipment for schools and hospitals in the developing world.
The royal couple have owned the car since 2013, when it was supplied new from Range Rover's VIP department.
It features a range of suitably regal extras, including heated memory foam seats, a Meridian sound system and a digital TV.
The auction house suggests the car could grow in value as first William, then George, take to the throne.
A spokesperson for Charity Stars, the auction house facilitating the sale, said: "The historic association of having served two future kings and a future queen is making this vehicle one of the most sought after in the history of royal vehicles.
"It has attracted significant global interest from families expecting their first-born child, as new parents will not only be able to enjoy the luxury and prestige of the car itself, but in being a part of the royal couple's historic story, during their 'once in a life-time opportunity' to drive their baby home from hospital."
Bidding on the car is already up to £49,970 ($65,216) ahead of the September 15 close date.
Royal second hand cars have sold well in the past, with the Queen's personal Daimler saloon achieving £45,360 ($59,126) in 2013.
Prince Philip's old 1954 Lagonda made a record £350,000 ($508,650) earlier this year.
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