This specific bolt is designed for Citroën 11CV and 15CV models. It's an M6 bolt with a length of 25 mm, used for securing the headlamp ring. This bolt is crucial for firmly fixing the headlamp opening, which is important for the headlamp's stability and positioning. Proper installation ensures that the headlamp does not shift while driving, vital for on-road safety and visibility. High-quality material guarantees durability under various driving conditions.