A pair of cover half members are attached to each other and to a seat hinge base plate in such a manner as to enclose the base plate. The respective cover halves each snap directly onto the base plate at a single point on their lower sides. At their upper sides the covers snap onto each other. The connection between the covers and the base plate is firm but is still resilient enough to allow sufficient movement between the cover assembly and the base plate in the event that large forces or shocks are applied to the cover. The connection between the cover halves is sufficiently strong that forces acting on the cover halves cannot readily force them apart nor cause them to become detached from the base plate.