The Rocker Shaft Support Retaining Ring for the Citroen 11CV 11D is a crucial engine component that ensures the stable operation of the rocker shaft. It helps maintain the correct position and functionality of the rocker shaft, essential for the engine's valve operation. Due to wear, it's important to replace this part timely to ensure engine performance and durability. This retaining ring is specifically designed for Citroen 11CV series models, providing a perfect fit and reliability, which helps prevent damage and ensures smooth engine operation.