Patent ID: 8348360

Claim:
An apparatus comprising a polyhedral sleeve forming at least one compartment, wherein the polyhedral sleeve has a plurality of hinged edges for switching between a flat folded condition and an unfolded weight-bearing condition, wherein the polyhedral sleeve comprises at least one floor face and at least one ceiling face; and at least one median wall, positioned within the at least one compartment and extending from the at least one floor face to the at least one ceiling face, wherein the at least one median wall is elastically biased by at least one biasing elastic element to hold the polyhedral sleeve in the unfolded weight-bearing condition, wherein the at least one ceiling face comprises at least one first eyelet for receiving the at least one biasing elastic element, wherein the at least one biasing elastic element is connected to the at least one ceiling face at the at least one first eyelet, wherein the at least one median wall comprises at least one second eyelet for receiving the at least one biasing elastic element, and wherein the at least one biasing elastic element is connected to the at least one median wall at the at least one second eyelet.