Tube

A long tube formed of an elastic material and including inner wall surfaces capable of supporting an inserted linear body, comprising:

• an upper portion including a printable upper surface;
• a lower portion facing the upper portion and including a lower surface;
• a first side wall connecting the upper portion and the lower portion;
• a second side wall connecting the upper portion and the lower portion and facing the first side wall;
• a first upper joint portion located at a connection portion between the upper portion and the first side wall and configured to bend the first side wall inward with respect to the upper portion;
• a first lower joint portion located at a connection portion between the lower portion and the first side wall and configured to bend the first side wall inward with respect to the lower portion;
• a second upper joint portion located at a connection portion between the upper portion and the second side wall and configured to bend the second side wall inward with respect to the upper portion;
• and
• a second lower joint portion located at a connection portion between the lower portion and the second side wall and configured to bend the second side wall inward with respect to the lower portion,
• wherein the first side wall includes:
• a first joint portion;
• a third joint portion;
• a first side wall upper portion provided between the first upper joint portion and the first joint portion;
• a first side wall lower portion provided between the first lower joint portion and the third joint portion;
• and
• a first side wall middle portion provided between the first joint portion and the third joint portion, and including an inner wall surface extending vertically with respect to the upper surface and the lower surface,
• wherein the second side wall includes:
• a second joint portion;
• a fourth joint portion;
• a second side wall upper portion provided between the second upper joint portion and the second joint portion;
• a second side wall lower portion provided between the second lower joint portion and the fourth joint portion;
• and
• a second side wall middle portion provided between the second joint portion and the fourth joint portion, and including an inner wall surface extending vertically with respect to the upper surface and the lower surface,
• wherein the first joint portion is formed to be thinner than a thickness of the first side wall upper portion and a thickness of the first side wall middle portion,
• wherein the third joint portion is formed to be thinner than a thickness of the first side wall lower portion and a thickness of the first side wall middle portion,
• wherein the second joint portion is formed to be thinner than a thickness of the second side wall upper portion and a thickness of the second side wall middle portion,
• wherein the fourth joint portion is formed to be thinner than a thickness of the second side wall lower portion and a thickness of the second side wall middle portion,
• wherein the upper portion includes a convex portion protruding downward on a center of a lower surface thereof,
• wherein the lower portion includes a convex portion protruding upward on a center of an upper surface thereof, and
• wherein, in a cross-sectional view,
• portions including the first side wall upper portion, the first upper joint portion, the upper portion, the second upper joint portion, and the second side wall upper portion are configured to be vertically symmetrical to portions including the first side wall lower portion, the first lower joint portion, the lower portion, the second lower joint portion, and the second side wall lower portion, respectively.