US Patent 6948203 Backpack convertible to a stretcher

A backpack includes an accommodating body, two slings, and a plurality of sliding plates. The accommodating body has a rectangular horizontal bottom wall, a front wall, a rear wall, and two side walls. The front, rear, and side walls extend upwardly from the bottom wall, are interconnected removably to define an accommodating space thereamong, and are removable from one another so as to be coplanar with the bottom wall, thereby forming a stretcher. The slings are fastened to an outer side surface of the front wall. The sliding plates are attached removably to a bottom surface of the stretcher, and contact the ground.