Collins Bus Corporation (Collins) is recalling certain model year 2013 model school bus and multi-functional school activity buses manufactured August 20, 2013, through November 13, 2013 and equipped with IMMI-brand L9 seat belt buckles. When the button is pressed to release the seat belt, the latch plate can become partially engaged with the buckle, making the seat belt difficult to unlatch. Thus, the buses fail to conform to the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 209, “Seat Belt Assemblies.”