Features: Small measures at 12"-14" Medium measures at 14"-16" Large measures at 15"-17" Extra Large measures at 17"-20" Contoured form-fitting design cradles knee. Superior foam system absorbs hard impacts. Streamline shape and design increases mobility. Seamless interior finish provides ultimate comfort. Ballistic nylon with industrial-weight stitching ensures durability. size specific caps create close contact with knee pad to minimize bulk.