This is a promotional souvenir ashtray produced for the Firestone Tire and Rubber Company exhibit at the 1934 Chicago World's Fair, known as A Century of Progress. The item features a miniature scale-model vulcanized rubber tire casing that holds a central amber pressed glass insert. The glass insert is centrally embossed with the text CENTURY / OF PROGRESS / Firestone / CHICAGO / 1934 and includes two molded cigarette rests. The rubber tire sidewalls are highly detailed with embossed markings including the Firestone brand name in script, a shield-shaped logo containing the letter F, and the words Gum-Dipped, NON SKID, and BALLOON. Technical specifications such as MAX. LOAD and MIN. AIR are also molded into the rubber sidewall. The tread pattern on the outer circumference consists of a repeating geometric non-skid design. Approximately 5.5 inches in diameter.