General Application - Great for alleviating knee pain and providing moderate knee joint stability.Medical Application - Patello-Femoral pain syndrome, Patellar tracking, chondromalacia, minor meniscus and ligament tearsHow it Works - Provides patellar (knee cap) stability with compression surrounding patella. Offers stability on medial and lateral sides of knee.Design Theory - Breathable, soft fabric offers 4 way stretch applying even, comfortable compression throughout brace. Thick oval gel provides excellent comfort and support to patellar (knee cap) area. Medial (inside) and lateral (outside) spiral stays offer overall knee joint stability.Sizing Chart Item # Sizing Measurement 7200 Small 13" - 14" 7201 Medium 14" - 16" 7202 Large 16"- 18" 7203 X-Large 18" - 20" (Circumference measured 1" above top of patella)