A hinge cap is a specific small part used in the classic Citroën 2CV. The cap is placed between the A-door and the B-pillar of the vehicle, serving as a protective cover for the door hinge. It not only aids in smoother door movement but also shields the hinge from dust and moist conditions, thus extending the lifespan of the components and preventing corrosion. For enthusiasts and restorers of the Citroën 2CV, this is an essential component to maintain the authenticity and functionality of the car.