The Bouclier Ventilation assembly is constructed from several parts from which the Air Shroud, Cylinder 4 is the most expensive.
Of all the components that make up this Bouclier Ventilation the Washer,spring has the lowest price.
Some items from this specific schematic: Screw, Crossreces (2e9), Washer,spring, Damper, Air Shroud 2, Fan.