OTC brand (model 2540) knee stabilizer. Orthotex fabric uses an open 3-dimensional knit that is a non-latex alternative to neoprene. It offers breathability, elasticity, therapeutic compression, comfort and heat control. It is less hot to wear than neoprene, thus appropriate for long term wear or wear in warm climates, and ideal for wearers who are allergic to or irritated by neoprene fabric. Opens flat for easy application over injured, swollen or tender knees. Four-way stretch material provides even compression over all the anatomical prominences of the joint. Elastic wraparound strap system, with single polycentric hinged bar, provides counter resistance and exerts corrective pressure to offload affected side of knee. Hinged bar is removable and shapeable if necessary. Interior condyle pads with different thicknesses can be adjusted for varying daily needs. Breathable and comfortable for long term wear. Fit by measuring around the bend of the knee. Available Sizes: X-Small (12-13 inch), Small (13-14 inch), Medium (14-15 inch), Large (15-16 inch), X-Large (16-17 inch), 2X-Large (17 -18 inch), 3X-Large (18-19 inch), 4X-Large (19-20 inch), 5X-Large (20-22 inch). Choose Left Knee (model 2425/L), or Right Knee (model 2540/R) both left and right can be worn either knees. Choose the left side insert if you have pain on the left side of either knee. Choose the right side insert if you have pain on the right side of either knee.