QUALITY MATERIAL: The main material of the product is silica gel, featuring a rotating bottle cap to prevent leakage. Designed with explosion-proof and scald-proof properties using high-temperature pressure shaping technology. Safe for microwave heating. NOTE: Fill with cold water and heat for no more than three minutes. SMALL AND PORTABLE: Size: 10.3 cm x 16 cm. Capacity: 320 ml. Suitable for adults and school-aged children. When filling, use hot water at a temperature below 80°C. Fill to two-thirds capacity for best results. Keep away from children and avoid contact with face during use. WARM HOT WATER BAG COVER: Soft, comfortable, removable, and washable. Knitted cover provides improved insulation and helps prevent direct contact with hot surfaces. Compatible with microwave heating. Do not use freshly boiled water. Keep out of reach of children when filled with hot water. MULTI-PURPOSE USE: Can be used for both hot and cold therapy. Heat application: helps soothe cold feet, non-inflammatory joint pain, muscle cramps, abdominal discomfort, and menstrual pain. Cold application: ideal for relieving sprains, swelling, toothache, and providing cooling relief during summer. WARM GIFT FOR COLD NIGHTS: A thoughtful gift for Christmas, birthdays, or New Year. Suitable for kids, teens, men, women, parents, and loved ones. Provides warmth during cold winter nights and can be used to soothe back pain and other body discomforts.