a double walled tubular flexible plastic package has an inflatable annular chamber surrounding an inner pocket . when an object is placed in the pocket and the chamber is inflated , the inner wall collapses inward to envelop the object . the inflation causes the flexible membrane to close off at the mouth of the pocket thereby substantially encapsulating the object being packaged . the object is essentially supported within a single air chamber thereby providing optimum cushioning from external forces and substantial insulation from external temperatures .