An oval facet (transverse costal facet) at the end of the transverse process articulates with the tubercle of its own rib.
Not all vertebrae articulate with ribs in the same fashion (Fig. 3.19):
The superior costal facets on the body of vertebra TI are complete and articulate with a single facet on the head of its own rib—in other words, the head of rib I does not articulate with vertebra CVII.