Small Fits Circum. 12 - 13.5 Elastic Support For Prevention Treatment & Rehabilitation Of The Knee Thermoskin Elastics Can Expand Contract And Stretch And Are Made Of A High-grade Durable Material That Permits A Full Range Of Movement And Are Comfortable To Wear During A Range Of Activities Anatomically Designed With No Seams This Four-way Stretch Support Combines Spandex With Hosiery Technology To Provide Protection And Support For Weak And Injured Knees