The Nut-hex is the lowest priced item on this Air Cleaner(klf400-b7) schematic.
A sample from the products for the Air Cleaner(klf400-b7) include: O Ring,50mm, Washer-plain-small,6m, Clamp, Filter-assy-air.
The Air Cleaner(klf400-b7) is made up of components including this Filter-assy-air which is the most expensive.