I purchased this knee support following a total knee replacement to strengthen the knee it is a perfect support for the job i have a size 15 inch knee and purchased a medium size it was tight at first bur after a few weeks it now fits like a glove on the kneefirst class service to ireland the only problem was with an post in ireland they could not find the tracking number on their records even though they had delivered the parcel could feel the difference as soon as i wore it