This "Just Like a Kotatsu" series, using patented technology to warm you from your feet, is designed for sleeping. For those who can't sleep because their feet are cold, or who feel anxious when they need to sleep, it offers three sleep-inducing switches to warm your feet and envelop you in a warmth just like a kotatsu. 【For Cold Protection While Sleeping】It thoroughly covers the soles of your feet, where blood vessels are concentrated, warming them all the way to your toes. The open-toe design allows for comfortable use while sleeping without your feet getting stuffy. 【Recommended as a Present/Gift】For those suffering from coldness or sleep problems, as a gift for family, friends, or loved ones. Perfect for birthdays, Mother's Day, Respect for the Aged Day, Christmas, and of course, as a reward for yourself. For a comfortable, warm sleep, just like a kotatsu, for that special someone, or for yourself. When washing, use a laundry net and wash with a neutral detergent. Also, while the materials used are excellent at retaining heat, they are prone to pilling due to friction from wear and washing. In such cases, please use a pill remover to care for them. Size: 22-25cm (for women) Unopened. #SleepSwitch #SleepSocks #Socks #ColdProtection #ColdFeet #JustLikeAKotatsu #SockSupplements