Parts such as the Rear Fender: Washer(6.5x18x1), Screw, Screw 6x12, Screw are included in the Gs450s 1987 (h) Finland Italy Austria (e15 E34 E39) Rear Fender parts fiche.
The component with the lowest price in the REAR FENDER schematic is the Washer(6.5x18x1).
On this parts fiche the Washer(6.5x18x1) is the most specified component.
