The Xtern AT set is a set of three "test orthoses" that are primarily used to evaluate whether an Xtern is a right orthosis for patients with drop foot. It can also be advantageously used as a training orthosis in rehab units. The Test orthosis is identical to the Xtern with the exception of the side blocks that allow the forefoot bar to be changed and adjusted. In the finished model, the side blocks are more integrated into the orthosis. With the help of the length and height measurements that the test orthosis is set to, later individual assembly of the Xtern is facilitated. The test orthosis is easily mounted with a plastic lock directly on the appropriate lace-up shoe, you can also mount the associated clips for easy removal and application.