Douglas Pro Arm Restraint limits the range of motion for players suffering from chronic seperation and dislocations. Features a multi-grommeted biothane belt, that requires drilling into plastic to attach. Sizing Info: Flexed Bicep Measurement (wrap soft tape measure around flexed bicep) S: 11'-12" M: 13"-14" L: 15"-16" XL: 17"-18" 2XL: 19"-20"