This is a used item! I purchased this from this site as a "new" item. I used it at home 2-3 times, but it was too effective for my stiffness, so I gave up. I think it will feel good for those with strong stiffness in their lower back and shoulders! I recommend that you can adjust it yourself and fit it to where you are stiff. Since this is a used item, please purchase it if you understand. ※Includes outer box and instruction manual The outer box is damaged. ☆The following is the seller's description at the time of purchase. [About the product] Introducing a unique stretching tool from the fitness club <Sports Oasis>, with two rows of balls. By using it while lying on your back, the balls arranged in two rows along the spine press on the muscles of the back, loosening muscle stiffness. Furthermore, by inserting the balls into the space between the shoulder blades, you can stretch while spreading the shoulder blades left and right. It can also be connected vertically and horizontally, and can be folded, rolled up, wrapped, and flexibly shaped, allowing for various stretches and exercises. It can be used on the floor or on a chair, which is a nice point as you can use it while doing other things. It comes with an easy-to-understand exercise guide with photos supervised by Oasis trainers. [Materials/Ingredients] ・Main body: Polyester, PVC ・Balls: EVA [Size] ・Approx. 52cm long x 22cm wide x 7cm high (1 piece) <When connected vertically> ・Approx. 99cm long x 22cm wide x 7cm high <When connected horizontally> ・Approx. 52cm long x 40cm wide x 7cm high ✽This is a secondary distribution product, regardless of whether it is used or unused, and there may be fine scratches that are difficult to see in the photos. Please refrain from purchasing if you are looking for perfection. ✽Due to lack of specialized knowledge, we may not be able to answer your questions. ※There may be fine scratches or crushed boxes that are difficult to see in the photos.