Neoprene Standard Knee Sleeve by Sport Aid is tapered in back for contoured fit. 12.5" long. Open patella model relieves pressure on the patella. Blue nylon exterior laminated to 1/8" of neoprene. Neoprene Hinged Knee Support with straps. Neoprene covered aluminum hinged stays have hyperextension stop at 170¶, one each medial and lateral. Universal buttress pad of felt attaches with hook to provide lateral, medial, inferior or superior patella support. Opposing loop-lock straps above and below patella. Measure around knee cap for size.