QUALITY MATERIAL: The main material of the product is silica gel, with a rotating bottle cap to prevent leakage. Designed to be leak-resistant and durable 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 warm water only (below 80°C), fill to two-thirds capacity, and avoid contact with children or your 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 fill with boiling water. Keep away from children when in use. MULTIPLE PURPOSES: Can be used for both hot and cold therapy. Heat application: helps relieve cold feet, non-inflammatory joint pain, muscle cramps, abdominal discomfort, and menstrual pain. Cold application: useful for minor sports injuries, swelling, physical cooling, toothache relief, and summer cooling. WARM GIFT FOR COLD NIGHTS: A thoughtful gift for Christmas, birthdays, or New Year. Ideal for kids, teens, men, women, parents, and loved ones during cold winter nights. Provides warmth and comfort for everyday use.