A remote controller includes a first balloon operation section, a second balloon operation section, a first balloon state display section, and a second balloon state display section. Each of the first and second balloon operation sections performs a pressing operation to swell or contract a balloon. Each of the first and second balloon state display sections has a swollen-state display portion and a contracted-state display portion. The swollen-state display portion is disposed along an outer circumference of each of the first and second balloon operation sections, such that the swollen-state display portion and each of the first and second balloon operation sections are coaxial with each other. The contracted-state display portion is disposed inside each of the first and second balloon operation sections, such that the contracted-state display portion and each of the first and second balloon operation sections are coaxial with each other.
