A reaction force generation unit includes an opposing member and a pressed body, which includes a base and domes, including a first dome, a second dome, and a third dome, bulging from the base. A leading end of each dome faces an opposing surface of the opposing member. When the pressing member presses the base, the leading ends of the domes move in a direction relatively close to the opposing member, where the domes become elastically deformed and cause an appropriate reaction force with respect to the handle. In a natural state where the pressed body is not subjected to any pressing force, axes of the domes are substantially parallel to each other, and acute angles formed by the axes and a normal line of the opposing surface are substantially similar to each other at a predetermined angle larger than zero degree.