A proton exchange polymer membrane whose surface is treated by direct fluorination using a fluorine gas, a membrane-electrode assembly, and a fuel cell comprising the same are provided. The side bearing includes a top member adapted to be located adjacent the car body of the railcar. A battery may be installed in a hollow post supporting the panel to provide power to the electrical devices. The image forming unit and the electrical component unit are respectively disposed on both sides of the feeder in a shorter side direction. The latch mechanism further includes at least one pawl rotably attached to the module such that when the lever arm is moved to the latched position, the lever arm rotates the pawl into a latched position wherein the pawl has an interference fit with the chassis.