Super Large (xxl) 18 -21 * Cho-pats Original Knee Strap Stabilizes And Tightens Up On The Kneecap Mechanism By Applying Pressure Upon The Patellar Tendon Below The Kneecap * This Compression Reduces Or Eliminates Inflammation And Helps Prevent Knees From Giving Out * Sizing: Based On Circumference Below Patella * Measure Leg Circumference Just Below The Kneecap * Offers Symptomatic Relief For Acute/chronic Pain Associated With Patello-femoral Syndrome And Osgood-schlatter's Disease. In Most Cases Jumper's And Runner's Knees Respond Well