J-Life Traditional Japanese Shiki Futon (Shikibuton) -TWIN SIZE EXTRA LONG with Custom Removable Asa No Ha Gold Cover 39" x 80" x 4" Traditional Japanese Futon - a true Japanese style mattress. Removable, washable cotton cover in one of our authentic imported Japanese fabrics. 5-Year Manufacturer's Warranty on Futon Cotton Mattress - no foam, wool, or innersprings Four Inch Thick Mattress Provides Portability and Firm Comfort