an alternative for instance when an inner container is desired for housing multiple products the internal dimensions of cavity 13 may be made to match the external dimensions of that inner container such an alternative may be desirable when multiple products are to be packed within a single inner container which is then given protective support within the outer shipping container in a broad sense the filled inner container then becomes the product to be stored or shipped as shown in fig1 product receiving cavity 13 in air bladder 11 is bounded by four respective corner elements 15 17 19 and 21 and by two respective side walls 23 and 25 although many examples of air bladder 11 will have corner elements the need for side walls will depend a good deal upon the specific application a relatively large product may for example require side walls between corner elements 15 and 17 and between corner elements 19 and 21 a relatively small product on the other hand may not require even the presence of side walls 23 and 25 air bladder 11 in fig1 is in accordance with an important aspect of the invention composed of a suitable plastic resin material.