This head bolt set is designed for various Citroën and Peugeot models, including the Citroën BX, C25, VI, XA, XS, ZX 16/19, and the Peugeot 205, 306, 309, 405, 406, 806 16/19. The set includes essential fasteners to correctly and securely mount the cylinder head onto the engine. These components are crucial for proper sealing and optimal engine performance. Using this set can help prevent engine issues by ensuring that the cylinder head is properly secured, contributing to the overall lifespan and performance of the vehicle.