First Class School Chair Support Kit, Large - 1 EachThe Support Kit for the First Class School Chair provides full support and extra security while using the chair. An adjustable trunk harness focuses support on the sternum and rib cage to prevent forward slumping and maintain correct midline seated position. Depth adjustable abductors position the users knees and help control spasti muscles that can cause legs to cross. Lateral supports that are height and width adjustable help to align and stabilize