This immobilizer is constructed of all new, black, durable open-cell foam, which can be trimmed for a custom fit. The three posterior stays and moveable dual medial/lateral stays provide proper immobilization and positioning. Also comes with a 4" elastic patella strap to lock out knee extension. Optional popliteal pad included. This immobilizer is ideal for post-operative immobilization; grade 1 and grade 2 collateral ligament sprain; patellar subluxations, and mild to severe knee injuries where full extension is required.