Abstract: A detachable transportation seat assembly for facilitated and secure attachment to the rear row of a mass transportation vehicle, which is releasable and replaceable as desired to enable access to vehicle componentry under the rear seat, or behind the rear wall. A pivot bar on the front of a single or a collection of rear row vehicle seats projects to cooperate with a pivot hook retention bracket, to facilitate removal of the seat or seats, or, alternatively, to facilitate the restoration of the seats for use by passengers.