Features: 1. High-Grade Material: This lunch ice crystal box contains dry ice crystals that are coarse and provide good expansion. The cold retention effect is strong. 2. Easy to Use: Ice crystals in the ice pack for lunch box will expand when absorbing water and freezing, so do not fill the pack completely when adding water; leave space for expansion. 3. Long-Term Use: If the liquid overflows during the expansion process, the ice pack can be cleaned and reused. With long-lasting cooling performance, it is reusable. 4. Wide Range of Uses: The refreezable ice pack is suitable for food refrigeration, breast milk storage, cooling for air conditioning fans, nursing, barbecues, travel coolers, and refrigerated transportation. 5. Suitable for Lunch Bags: After receiving the ice brick pack, add water to activate. The ice crystals will expand after water absorption. Once expanded, freeze in the refrigerator for 2–4 hours before using with lunch bags. Notice: 1. Actual color may vary slightly due to different monitor settings and lighting conditions. 2. Please allow 1–3 cm deviation due to manual measurement. Material: PE Size: 15.8 x 4 x 4 cm Includes: 1 x Ice Crystal Box