S size (6 inches): Applicable to children under 10 years old, M size (9 inches): Applicable to adolescents. This product is essential for sports injuries, pain relief, muscle aches, and first aid. Large diameter & good temperature control. The large diameter makes it easy to put in ice, and the temperature can be maintained for a long time. It is economical because it can be used repeatedly, and it is compact and easy to store even when going out. Not only for icing, but also a cold and hot pack that can handle temperatures up to 50 degrees Celsius, so it can be used for chronic pain or when warming a cold affected area. It is also recommended for relaxing stiff muscles. Relieves body fatigue and pain. Icing relieves muscle pain and suppresses swelling caused by inflammation. Suitable for sudden fever, headaches, toothaches, and heatstroke. Relieves menstrual pain in women. Excellent safety and leak-proof & waterproof - Made of polyester material, improving leak-proof performance. It prevents the loss of temperature and can maintain the water temperature for a long time. It is also easy to carry and can be used anywhere. Relieves pain and fatigue? The ice bag pack is ideal for cold therapy, reducing pain and swelling from minor injuries, bruises, muscle aches, sprains, and strains, and is suitable for sports injuries and emergencies. 2632