This hex socket diaphragm bolt is suitable for installation in the brake or clutch system of a later production Citroën DS. The bolt provides a solid connection between components that operate under pressure. The diaphragm helps to distribute forces in the system in a balanced way. The metric thread and M8x20 dimensions make this bolt fit on prepared mounting points. It can be used during maintenance or repair of hydraulic parts. The design supports reliable system operation and helps to limit leakage and wear of surrounding components in regular workshop use and repeated assembly.