Polyester fiber HOME USE OR SPORTS: Ice packs for injuries are daily necessities, especially for athletes, helping to reduce various types of pain quickly for improved comfort. COLD TREATMENT: Ice bags are effective for headache, migraines, toothache, muscle spasms, joint pain, swelling, and minor sores. The ice bag stays cold for at least 4 hours; adding alcohol with ice cubes may extend cooling time. HOT TREATMENT: Hot packs help relieve menstrual pain, arthritis, and back pain. Note: The recommended temperature for hot water therapy is 5060C (122140F). GET RELIEF ANYWHERE FOR ANYONE: Includes 3 reusable ice bags in different sizes (11", 9", 6") and 1 elastic wrap. The 6" pack is suitable for children or small body areas (eyes, neck, ankle, elbow, etc.), the 9" for teenagers and adults for medium areas (teeth, knees, head, etc.), and the 11" for adults for larger areas (back, shoulders, etc.). NO LEAK AND SKIN-FRIENDLY FABRIC: Made with high-quality materials to prevent leaks during use. The soft fabric is gentle on the skin.