The donjoy reaction web knee brace uses a responsive, webbed approach to knee pain that gives you a distinct alternative to the basic knee sleeve. Developed by world renowned orthopedic surgeon, dr. William nordt, the reaction web can help decrease knee pain and increase function to get you back to your active lifestyle. The elastomeric web is an innovative solution that absorbs shock, disperses energy and shifts pain away from your knee. This webbing acts to dynamically stabilize the patella on all sides, bringing the patella into proper tracking position to reduce pain. The open framework of the elastomeric web, in combination with the mesh backing, creates a comfortable fit and a breathable solution for relief of anterior knee pain. The reaction web is secured with velcro straps, and weighs only 0.5 lbs. The lightweight design makes this knee brace ideal for all-day use. The reaction web knee brace can be worn on either the left or right leg, and with or without the undersleeve. One undersleeve is included, and is made of 85% nylon/15% spandex. The reaction web can be used to treat or prevent the following knee injuries: patellofemoral pain syndrome (PFPS), chondromalacia patella (runner's knee), quadriceps or patellar tendonitis/tendinosis (jumper's knee), osgood-schlatter disease, general patellar tracking issues and instability, and mild knee osteoarthritis. The reaction web is worn by professional snowboarders, volleyball, football players; as well as the U.S. Snowboarding and U.S. Ski teams.