This flat washer sits between a fastener head and the mounting surface on a harvesting machine assembly. It distributes the clamping load over a wider area than the fastener alone, preventing localized deformation of the component it secures. A missing or deformed washer can allow the fastener to loosen under vibration, leading to misalignment of the attached subassembly. The washer is manufactured to the original dimensional specification, so its inner and outer diameters match the fastener shank and the boss face without interference. On reinstallation, ensure the washer is seated flat and free of burrs.