On this parts fiche the Bolt,flanged,6x25 is the most specified component.
The thirty-five Kx450-fef Kx450f 2014 Usa Engine Cover(s) component parts are all listed in this schematic.
The most reasonably priced component used on the Kx450-fef Kx450f 2014 Usa Engine Cover(s) is the Bolt-flanged-small,6x.