Mueller-exclusive hydracinn fabric is the moisture-wicking catalyst for maintaining superior support with heat management. Base sleeve is made of antimicrobial fabric that is uniquely breathable, extremely soft to the touch with flatlock seams, and features a conforming hourglass design. Inner grip strips complete the anti-sweat/non-slip design to help prevent brace migration and preserve high-performance support. This ultimate brace provides maximum support for weak or unstable knees, as well as protection after injury. Features upper strapping system locks brace in position. Outer mesh shell with bidirectional stretch fabric fastens on the sides then comfortably locks across the quadriceps. Patented triaxial hinges provide maximum protection with near-normal knee motion. Tibial containment system features a custom secondary shell with stabilizing patella buttress and rear support strap. Sizing sizing measure around center of knee 12-14in 30-35 cm small 14-16in 35-40 cm medium 16-18in 40-45 cm large 18-20in 45-50 cm x-large 20-22in 50-55 cm xx-large.