Some items from this specific schematic: Cover,air Filter Case, Case-air Filter, Bolt,w/washer,6x12, Holder,air Filter Cas.
With a quantity of four pieces, the Nut,flanged,5mm is the most used part in the AIR FILTER diagram.
The lowest price component in this Air Filter parts-list fiche is the Washer,6.5x20x1.6.