摘要 |
A vent plug wherein breakage of an air permeable membrane is prevented by means of a projected part of a cylindrical member, but a liquid is not likely to stay inside. Specifically disclosed is a vent plug comprising a cylindrical member (1) having a through hole (1a), and an air permeable membrane (2) attached around the cylindrical member (1). The air permeable membrane (2) has an attached region which is in contact with the cylindrical member (1), and an air-permeable region facing the through hole (1a). The cylindrical member (1) is provided with a projected part (1b) which projects beyond the plane including the air-permeable region, and the attached region of the air permeable membrane (2) has a shape following a part or the entire of the projected part (1b). |