Although unused, it has been opened once, so please understand. Mattress Cover, Warm Sheet, Futon Compatible, Approx. 30cm Gusset, Housecover (Double, 140x200cm, Gray) [Warm Contact Temperature & Heat Retention Function] This winter fitted sheet uses high-density premium flannel fabric. The microfiber is densely packed, trapping a lot of air in the pile, which effectively locks in warm air and provides excellent heat retention. You'll be enveloped in fluffy warmth the moment you get into bed. It's an essential item for chilly autumn and winter. [Meltingly Soft Touch] The softness of the fabric is determined by the length and fineness of the pile. The Housecover winter fitted sheet uses 220g/㎡ high-density ultra-fine flannel material. The fine fibers are densely packed, making it fluffy and soft, and you'll become addicted after just one touch. [CICA Moisturizing Ingredient Coating] The CICA (Centella Asiatica Extract) ingredient, popular in the cosmetics industry, is also used in the fabric of this sheet. It reduces static electricity and makes it difficult for dust and pollen to adhere. The natural moisturizing ingredients last longer than conventional anti-static treatments. It also enhances the softness of the fabric and helps moisturize the skin and prevent roughness. [Easy to Put On and Take Off, Full Elastic Band] This fitted sheet has an elastic band all around for a secure fit on mattresses from 3 to 28 cm thick. It's less likely to shift or wrinkle, making bed making smooth every morning. It securely wraps around the corners of the mattress. [Machine Washable & Static Prevention] It can be washed at home, so you can always use it clean and hygienic. When using a washing machine, be sure to use a laundry net. It is treated to suppress static electricity, reducing stress in winter. It also prevents dust from clinging due to static electricity. [Quality & OEKO-TEX Standard] Our fitted sheets are planned and designed in Japan and manufactured in a factory certified by OEKO-TEX Standard 100, which guarantees that textile products meet high safety and environmental standards. It delivers safe and healthy sleep, even for those with sensitive skin. [Specifications] Fitted Sheet Size: Double, 140x200x30cm gusset. Material: Ultra-fine flannel fabric (CICA moisturizing treatment + photocatalytic antibacterial treatment). Full elastic band for easy on/off, fits mattresses/futons from 3 to 28cm thick.