A case body includes a distal end side case configuring a part of a case body exterior, a center portion case disposed in a position adjacent to the distal end side case and configuring a case body exterior in conjunction with the distal end side case, a first elastic seal member disposed to be exposed as a case body exterior in a boundary between the distal end side case and the center portion case provided adjacent to each other, and an abutting section configured to set a crushing amount of the first elastic seal member, the abutting section including an abutting surface provided in one of the distal end side case and the center portion case and coming into contact with a bottom surface of another exterior member.
