removed from the container the liquid evaporates to replace it keeping the pressure in the cylinder constant however when the remaining liquid decreases the area of outer wall in contact with liquid also decreases the outer wall temperature it is controlled by both the ambient room temperature and the cooling effect of the liquid produced when gas is being drawn from the container as the area of outer wall in contact with the liquid decreases the rate of heat exchange decreases thereby the liquid temperature can no longer be maintained and the liquid vapor balance is not sustainable resulting in a pressure drop that is not stable however if a stabilizing device is wrapped around the liquid area of the base of the cylinder providing a greater rate of heat exchange the pressure stability is maintained accordingly an embodiment of the present invention includes a collar and fin unit constructed with a material that absorbs and transfers heat such as for example aluminum alloy which is a material commonly used for heat sinks as well as other materials that are capable of transferring heat preferably the material should be mechanically soft enough to compress around the cylinder and be held tightly.