PROBLEM TO BE SOLVED: To provide a stretchable member which can maintain a stretched state.SOLUTION: A stretchable member 1 includes: a crest part 21 which is convex outwardly in a radial direction； a trough part 22 which is convex inwardly in a radial direction； an accordion part 2 having a plurality of middle parts 23 connecting the adjacent crest part 21 and trough part 22 and stretchable and shrinkable in an axial X direction； and a cover 3 having an elastic body, covering an outer surface of the crest part 21 in a radial direction and pressing the crest part 21 in the axial X direction of the accordion part 2 by elastic force of the elastic body. The outer surface of the crest part 21 is covered by the cover 3, while an outer surface of the trough part 22 is exposed.SELECTED DRAWING: Figure 1【課題】収縮状態を維持することができる伸縮部材を提供すること。【解決手段】伸縮部材１は、径方向外側に凸となる山部２１と、径方向内側に凸となる谷部２２と、隣接する山部２１と谷部２２とを繋ぐ中間部２３とを複数有し、軸Ｘ方向に伸縮する蛇腹部２と、弾性体を含み、山部２１の外表面を径方向に沿って覆い、弾性体の弾性力によって山部２１を蛇腹部２の軸Ｘ方向に向かって押圧するカバー部材３と、を備え、山部２１の外表面がカバー部材３により被覆され、谷部２２の外表面が露出している。【選択図】図１
