Provides additional support & stability for the medial lateral ligaments.Its 2 hook & loop straps allow adjustment for a better fit.The additional neoprene circle pad around the patella provides padded protection and stabilisation to prevent patellar displacement.Size:Measure around mid-section of the knee while in a standing position. 11⅛ - 12⅞13 - 1414⅛ - 1515⅛ - 1717⅛ - 20 (29.2-32.7cm)(33-35.6cm)(35.9-38.1cm)(38.4-43.2cm)(43.5-50.8cm) X-Small. Small. Medium. Large