U.S. patent application 20180370681 (applicant Airdex Corp., Newport Beach, Calif.):
"The present invention provides a movable load bearing structure having indentations, grooves, valleys, channels or other similar depressions on its underside. These depressions are mated with corresponding features for improved loading bearing capabilities. The load bearing structure may be a dunnage platform or a container for storing and/or shipping cargo. ... In an embodiment of the invention ... pockets may be used to locate phase change materials."