Pillar

The A-pillar of a vehicle is the first pillar of the passenger compartment, usually surrounding the windscreen. The A-pillars play an important role in protecting the occupants in a roll-over incident, consequently A-pillars have been increasing in width over the years. However this has caused the adverse effect of increasing the size of blind spots in the drivers vision, especially at junctions.

The B-pillar of a vehicle is the second pillar of the passenger compartment, after the A-Pillar. B-pillars are also used to house the hinges for any rear doors, or the latch for a car fitted with suicide doors. The B-pillars also play an important role in protecting the occupants in a roll-over incident, consequently B-pillars, like A-pillars, have been increasing in width over the years.

The C-pillar is a pillar that supports the back window and the rear part of a vehicle뭩 roof. From the point of view of nomenclature, even if there appears to be no B-pillar between the front and rear doors of a car, the rearmost pillar is generally labeled C. On a vehicle such as an SUV or MPV, with three windows along the side, the C-pillar is the third (rear door) pillar and the rearmost pillar is the D-pillar.

The cant rail of a vehicle is the structural member which runs over the top of the doors. The cant rail of a vehicle is supported at the front by the A-pillar, and depending on the number or doors, a B, or C-pillar at the rear. The cant rail can also act as a housing for curtain airbags if the vehicle is equipped with this feature.