The Washer(5.5x18x1) is the most widely applied product in the GSXR600 1999 (X) HEADLAMP (E2, E24) ( six times ).
Of all the components that make up this Headlamp (e2, E24) the Bulb(12v5w) has the lowest price.
Some items from this specific schematic: Headlamp Assy, Bulb(12v55/50w), Screw,side Hol, Bulb(12v5w).