A conditioning agent (typically for use in repairing a flaw in a glazing panel) is contained in a sealed container which is itself disposed internally of a flexible outer walled container. Pressure applied to the outer flexible walled container can cause release of the conditioning agent from the internal conditioning agent container. The conditioning agent preparation may comprise a hygroscopic solvent (such as acetone) combined with one or more primer additives to prime the surface of the glazing panel for repair.