| 摘要 |
The insertion instrument is provided with a first flexible tube section with a lower flexibility than the spiral tube, and a second flexible tube section with a flexibility that, when not covered by the spiral tube, is lower than the spiral tube and is the same as or higher than the first flexible tube section. By covering the outer circumference of the second flexible tube section with the spiral tube, the flexibility becomes lower than the first flexible tube section. The insertion instrument is provided with a third flexible tube section on the base end side of the second flexible tube section with a flexibility that is lower than the first flexible tube section. |
