Sealing plug

A sealing plug for sealing a hole in a wall, which sealing plug is insertable into the hole by access from only one side thereof, which sealing plug comprises:

• a radially expandable body which is radially expandable by access thereto from only a first end thereof,
• a sealing cap which covers a second end of the expandable body and extends therefrom along the exterior of the length of the expandable body, the sealing cap being of a material which is fluid resistant;
• and
• retention-assisting means for retaining the sealing cap on the expandable body, wherein the retention-assisting means comprise an axial indentation of the first end of the expandable body that forms a local radial expansion of the expandable body into engagement with the sealing cap to retain the sealing cap on the expandable body;
• wherein a radial cross-section of the sealing plug proximate to the first end of the expandable body is no greater than a radial cross-section of the sealing cap proximate to the second end of the expandable body;
• whereby, when the sealing plug has been inserted in the hole and has been radially expanded so that at least part of the sealing cap adjacent the wall of the hole expands and engages therewith, the sealing cap is secured in the hole with the sealing cap sealing the expandable body against access thereto from outside the sealing cap.