What is the Donjoy Rotulax Knee Open Patella? The Donjoy Rotulax Open Patella Knee provides assurance & piece-of-mind for those suffering from patella instability & is ideal as a post-operative support. With built-in flexible bilateral stays & a silicone patella buttress the Rotulax is a prophylactic brace which can be used for daily living or non-impact sports. Weighing less than 500 grams this multi-use latex-free brace is perfect for use over extended periods & can be utilised as an injury treatment or prevention measure. Anatomically knitted from a Polyamide, Cotton & Lycra multi-directional fabric Encourage proprioceptive & neuromuscular stimulation through compression Patellofemoral injuries & mild osteoarthritis This support is suitable for either the left or right knee What size do I need? The thigh circumference should be taken 15 cm above the patella mid-line & where your sizing falls between measurements, please select the next size up: Small: 35-38 cm or 13-15.5 inches Medium: 39-42 cm or 15.5-16.5 inches Large: 43-46 cm or 17-18 inches X-Large: 47-49 cm or 18.5-19.5 inches XX-Large: 50-53 cm or 19.5-21 inches XXX-Large: 54-57 cm or 21-22.5 inches This product is not suitable for contact, extreme or water-based sporting activities. Please Note if buying from abroad: These products are sent direct from the manufacturer & so lead times will be significantly longer than normal if you purchase this item from outside the UK