Roof pillars

The steel pillars that surround the front and rear windshields and front and rear doors in a sedan. Pillars between the windshield and the front door are referred to as A-pillars. Pillars between the front and rear doors are referred to as B-pillars. Pillars between the rear doors and the rear windshield are called C-pillars. They provide greater rigidity to the car and making a hardtop possible.