Exos FORM II 621 Back SI SupportDesigned with the Patient in Mind. Designed to be as light weight and low profile as possible without compromising form and function. Provides relief from mild lower back pain and superior sagittal control and support from L 1 to L 5. Exos Form II 621 Thermoformable Panels A quick and easy way to ensure a personalized fit. Preformed 3D Contours The Exos Thermoformable panels come preformed to a specific shape and can be worn by the patient straight