Abstract: An inflatable support, kit of parts for forming a system for immobilizing a human leg, and a method of preparing an inflatable bag for supporting a human leg. The inflatable support includes a bag that has a single body having a first surface and a second surface. The body of the inflatable bag is made up of multiple air chambers running generally throughout. Portions of the bag between adjacent air chambers of the body form joined regions, such as notches, that allow the inflatable bag to bend to conform to the contours of a human leg. The inflatable bag body has a valve attached thereto so as to allow an inflation medium to pass into one or more of the air chambers.