A Chrysler 300F Convertible, one of the legendary "Letter Cars", will see some of the top bids at this year's Auburn Spring sale, held on May 8-10 by Auctions America.

The Letter Cars were predecessors to the American muscle car, combining power and style

Predecessors of the American muscle car, the Letter Car 300 series was produced with a focus on performance from 1955 to 1965, using a new letter of the alphabet for every new model.

The 1960 convertible is valued at $150,000-175,00, hailing from the Rigoli Letter Car Collection. A line-up of cars from the collection will feature alongside the Duffy Grove Collection and John Scotti Collection in the sale.

Letter Cars were advertised by Chrysler as "the Beautiful Brutes", a fitting title given their combination of style and power. One of only 78 300Fs known to survive, this example is considered one of the finest, having received a full restoration.

The Phantom VI finally ceased production in 1991, with just 374 cars produced during the 24 year run

Leading from the John Scotti collection is a Rolls-Royce Phantom VI limousine from 1970, which is valued at $130,000-160,000.

Continuing the unparalleled luxury of the Phantom VI series, the Phantom VI was released more than 40 years after the first model and was designed with the company's top costumes in mind. Just 374 cars were produced over the Phantom VI's 24 year run, and each were fulled with custom, handcrafted bodies inLondon.

The example at auction is "arguably one of the finest in the world", according to Auction America, who add: "One does not have to be a royal to appreciate this automobile, but will feel as such upon arrival. Madam and sir, your motorcar awaits you."

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