gymterior SWING TETRA New Unused [Although the photo shows blue, this is the gray one for sale] One gray piece Retail price: 21,780 yen each For shipping, we will wrap the original cardboard box with stretch film. The following is an explanation from the official HP: Abdominal muscle support with the power of a pendulum Sofa cushion A sofa cushion that targets abdominal muscles just by leaning back. Furthermore, it assists abdominal exercises easily with the power of a pendulum, like a rocking chair. It uses a soft-touch fabric used in high-end furniture. You can use it not only for "while-doing" diet but also comfortably as a sofa cushion or pillow to lean back on.