The Screw, Pan Head is the lowest priced item on this Rear Master Cylinder schematic.
Parts such as the Rear Master Cylinder: Screw, With Washer (5u8), Joint, Diaphragm, Reservoir, O-ring (34j) are included in the Yz125 1989 (k) Usa Rear Master Cylinder parts fiche.
The Yamaha REAR MASTER CYLINDER has twenty products enlisted in the schematic.