The Closed Knee Support 706 by LP Support provides firm support and compression for weak or overstressed knees. The closed cell neoprene used retains heat, helps circulation, and aids healing. Useful for strains, arthritis and protection against abrasions, this support is easy to slip on and off... Measure around mid-section of the knee while in a standing position. 29.2-32.7cm-XS... 33-35.6cm-S... 35.9-38.1cm-M... 38.4-43.2cm-L... 43.5-50.8cm-XL...