Valve stem assemblies

An assembly, comprising:

• a straight rigid hollow tube and a compression sleeve mounted to the hollow tube;
• wherein the hollow tube is at least partially threaded on its exterior surface extending along a middle of its exterior surface and a flange at a distal end to retain a distal end of the compression sleeve while under compressive forces;
• wherein the compression sleeve is made from a flexible, deformable and compressible material;
• wherein the hollow tube and compression sleeve are configured to be partially insertable through a wall opening from a first side of the wall through to a second side of the wall, and
• a mechanism accessible from the first side of the wall to compress the compression sleeve against the second side of the wall
• wherein the compression sleeve while under compressive forces forms a void between an inner wall of the compression sleeve and hollow tube,
• wherein the compression sleeve expands against the wall opening and against the second side of the container;
• and
• wherein the mechanism accessible from the first side of the wall to compress the compression sleeve against the second side of the wall comprises at least one nut configured for mounting to the external threads on the middle of the hollow tube, whereby when the nut is rotated, the hollow tube is partially retracted from the second side.