Some items from this specific schematic: Bolt,flange,6x55, Washer C,8mm, O-ring,13.8x2.5, Cover Comp.cyln.h.
In this schematic the "Washer C,8mm" is used most often.
This part-list fiche shows all the components that make up the Cn250 Helix 1996 (t) Switzerland Kph Cylinder Head Cover .