This is a two-disc set originally sold on a certain channel for 19,800 yen. I haven't used one of the discs, so I'm putting it up for sale. The images are of the one I'm using; the one for sale hasn't been taken out of its bag. It provides moderate support to support your knees. Supervised by Dr. Akira Kawamura, a pioneer in knee health, who has written many books and appeared in numerous media outlets. Developed based on Dr. Kawamura's "knee back stretching theory," which states that when you bend your knees, your upper body tilts, and you try to maintain balance, your posture gradually worsens. By wearing it, these spats support the stretching of the muscles behind the knees, which are the starting point for stretching the body.