The component with the lowest price in the Wheels/Tires schematic is the Nut,12mm.
With all the components that make up the KAF620-PCF MULE4000 2012 USA Wheels/Tires assembly. The Nut,12mm is the most frequently specified with sixteen applications.
The four Kaf620-pcf Mule4000 2012 Usa Wheels/tires component parts are all listed in this schematic.