The RSSâ„¢ Rucksack Stretcher System from the British firm Centurion is exactly what it is called. It is a day pack that converts into a stretcher. There is a removable daypack consisting similar to the Crusader/PLCE design consisting of zippered side pockets as well as a first-aid kit. Additionally, the RSS can be configured with an optional lightweight backboard. There are also integral straps which can be used to immobilize the casualty.
In the stretcher mode, it can be configured for carry by two to four bearers and can be reinforced with makeshift poles.
The RSS comes in Red, Black, Woodland, or Desert but custom colors can be accommodated. Check it out over at rucksackstretcher.com.