Hardtop

A hardtop is a rigid form of automobile roof. They may be detachable for separate storing, retractable within the vehicle itself, or permanently attached to an auto lacking a center side-support known as a B-pillar. The term is also used to describe such vehicles, principally the last.

Hardtops may be either two-door or four-door, and tend to be more expensive and collectible than sedan models of the same vehicle.

Early automobiles were open, described as having a "torpedo", "runabout", "phaeton", or "touring car" bodystyle. In time, some were made with rudimentary weather protection composed of a convertible-type canvas top and celluloid or isinglass side curtains. Some instead had removable rigid roofs, which were cumbersome and laborious to seasonally alternate.

Once fully closed bodies became the norm, it was considered fashionable to remove the central roof support post to give them a more open touring look. The first "hardtops" appeared during the 1915–1918 era as "convertible cars", marketed as "touring sedans" or "Springfields" because many automakers had the bodies built by Springfield Body Company under license from Fisher Body and others. The Springfield design featured folding upper frames on the doors and the rear glass frames is removable and stored under or behind the seats.

By the time of World War I some automakers offered a removable roof, typically with a wood frame with a canvas or leather covering, that bolted onto touring car or roadster bodies. They typically used side curtains like the conventional folding soft tops.

The elaborate cloth covered "California top" originated in the West, with either a permanent or a folding frame. These were designed with an emphasis on proportions to accent and provide distinctiveness to the appearance of the automobile, with colors adding special accents. One objective of these aftermarket tops was to bring the cost of the closed car nearer to the prices of corresponding open cars. Automobile dealers were encouraged to equip an open car with a California top to demonstrate that they were "cool and clean in summer, and warm and dry in winter." The hard tops were frequently equipped with celluloid windows that retracted like a roller blind for open sided motoring offering a low-cost compromise between an open and closed car.

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Wikipedia