FREEZE & HEAT THERAPY - WORLD-BIO small round gel packs can be safely utilized for both hot and cold application. For cold therapy, all you have to is place the ice pack in the freezer for at least 30 minutes. For hot therapy, place the gel pack in the microwave or the hot water. REUSABLE & FLEXILE - The freezable gel pads will keep soft and flexible even after storing in the freezer. Soft cloth backing is too cozy to hurt baby soft skin. With its handy size (4-inches in diameter), cooling packs can be placed comfortably on any part of your face and body. NATURAL VERSATILE SOOTHING RELIEF - Medical ice packs are safe and natural relief for tired puffy eyes, fever, toothaches, bumps or bruises. It also can be used for beauty or skincare in clinical, reduce inflammation for breast augmentation, decrease engorgement unclog ducts relieve mastitis increase milk production, and even as a boo boo ice packs for children's injuries.