Abstract: An apparatus for mounting signaling articles to a vehicle. In an embodiment of the present disclosure, the apparatus comprises a plate comprising a first surface and a second surface; an expansion fitting comprising a first surface and a second surface, wherein the first surface of the expansion fitting is oriented toward the second surface of the plate and the expansion fitting comprises a flexible material; a securing bolt comprising a head and a threaded portion, the threaded portion being inserted through a hole in the plate and a hole in the expansion fitting; and an attachment nut wherein and end of the attachment nut is threadably engaged with the threaded portion of the securing bolt.