The Washer,plain, 8mm is the lowest priced item on this Exhaust Muffler schematic.
A sample from the products for the Exhaust Muffler include: Bolt Flange 6x18, Washer,und, Gasket Exh.valve (nas), Joint Comp.exh..
Of all the components used in this assembly the Muff.comp. is the most expensive.