I'm selling this because I switched to Bauerfeind. It has more signs of use than item ①, which is also listed. From the manufacturer's website: ● Lightly compresses and warms the entire knee. ● Open-knee design allows for smooth bending and extending of the knee. ● Short sleeve type, 25cm long, that supports movement without hindering it. ● Four-way stretch neoprene rubber provides a snug fit.