"The ultimate warmth created by ultra-fine flannel." Using fibers even finer than standard flannel. By containing plenty of air, it achieves outstanding heat retention while remaining lightweight. It's characterized by a soft, gentle enveloping feel from the moment it touches your skin. It blocks the coldness from the mattress and promises a warm sleeping space until morning. "Stress-free cleanliness." Dust and pollen are less likely to adhere to the sheet surface, allowing you to maintain a cleaner state even if you are concerned about allergies. The effect lasts even after repeated washing, so you can use it with peace of mind. "Warmth that gently spreads while you sleep." It uses "moisture-absorbing heat generation" material that quickly absorbs sweat and moisture during sleep and converts that energy into heat. It's less likely to get stuffy, and a comfortable, warm feeling lasts throughout the night. In addition, the densely woven structure makes it difficult for pilling and shedding to occur, maintaining a beautiful appearance and comfort for a long time. "Easy-to-install box design." The all-around elastic design that completely covers the mattress makes it easy to install, even on thick mattresses. It fits snugly even if you toss and turn in your sleep. With its refreshing absorbency and breathability, it's cool in the spring and summer and provides heat retention in the fall and winter. You can spend a comfortable year-round. 【For winter and cold seasons】This sheet is perfect for the cold season to the extremely cold season. You will immediately feel the overwhelming fluffy warmth as soon as you lie down on the bed. It has elastic all around, is easy to put on and take off, and perfectly wraps the corners of the mattress. It is produced in a factory that has been producing bedding for many years, so the quality is also reliable. Warm box sheet single for winter Warm sheets Bed cover Microfiber sheets Cold protection for winter Warm Moisture-absorbing heat generation Smooth Bed cover Mattress/futon compatible (Single・100X200cm Gray)"