Easy to use: Add water to activate the expansion of the ice crystals, then freeze for approximately 2 to 4 hours. A practical solution for maintaining a low temperature in your lunchbox throughout the day, without complicated handling. Versatile applications: Perfect for storing breast milk and refrigerating food, these ice packs are suitable for refrigerated transport and complement ventilation/air conditioning systems. An efficient cooling solution for everyday needs, with broad compatibility and consistent reliability in various scenarios. Portable comfort: Designed for practicality, its minimalist size and light weight ensure effortless insertion into any bag, providing a convenient way to take cold drinks with you wherever you go. Extended coldness: The coarse-textured ice particles with high expansion capacity ensure excellent cold retention, keeping lunches and drinks chilled for longer. Long-lasting use: The robust construction of thickened PE ensures impact resistance and sustained durability during regular use of this reusable ice pack.