Four-door hardtop

This is a four-door car styled to resemble a convertible, but having a rigid top of metal or fiberglass. Buick introduced a totally pillarless design in 1955. A year later most automakers offered equivalent bodies. Four-door hardtops have also been labeled sports sedans and hardtop sedans. By 1976, potential rollover standards and waning popularity had taken their toll. Only a few makes still produced a four-door hard-top and those disappeared soon thereafter.