Just drop in a full bag and go: The Expedition offers 6.4 cubic feet of fully usable, wall-to-wall bed bug heat treatment capacity. Great for working through big batches of items. Includes two heavy duty liner bags and corded thermometer. The Expedition is constructed with a UL-recognized thin heating film that evenly distributes the heat around the walls of the box. This ensures there are not excessive hot spots that could damage the contents, or cold spots allowing the bugs to hide. The walls and floor of the Expedition System can safely heat up to 160°F to surround the contents with uniform heat to permeate the core, yet is safe to touch and won’t damage the contents, the company says.