On this parts fiche the Washer,plain,4mm is the most specified component.
The Fuel Meter / Temperature Meter assembly is constructed from several parts from which the Regulator, (7v) is the most expensive.
A sample from the products for the Fuel Meter / Temperature Meter include: Clip,wire Harness, Stay, Meter Set, Washer,spg.,4mm, Screw-wash.,5x12.