This is an extra-fine flannel sheet for a double bed. It uses heat-generating material. It has rubber bands on all four corners. Please check the size, material, etc. in the photos. I bought it but never used it and have stored it at home. Please consider this before purchasing. It will be packed in recycled materials and shipped via Yu-Yu Mercari Delivery or Raku-Raku Mercari Delivery. Thank you for looking.