Seirus Padded Patella Hyperflex Insert. Breathable Neoprene. Superior compression and warmth from closed cell neoprene. Padded patella locator relieves pressure and helps prevent patellar injury. Nuclear Knee adds technical locking, dual pivot, metal hinges to help prevent hyperextension, pull on loops and Velcro adjustable support straps. Small 13.25 "-14.5 " Medium 14.75 "-16 " Large 16.25 "-17.5 " XLarge 17.75 "-19 " XXLarge 19.25 " Seirus Padded Patella | Black | Medium | Christy Sports