Features: 1. High-Grade Material: This lunch ice crystal box contains dry ice crystal particles that are coarse and offer good expansion. The cold storage effect is strong. 2. Easy to Use: Ice crystals in the ice pack for lunch box will expand during the process of absorbing water and freezing, so do not fill to the top when adding water; leave space for expansion. 3. Long-Term Use: During the expansion process of the ice pack for air condition fan, if the ice crystal liquid overflows, it can be cleaned and reused. With long-lasting cold retention, it can be used repeatedly. 4. Wide Range of Uses: The refreezable ice pack is suitable for food refrigeration, breast milk preservation, air conditioning fan cooling, nursing, barbecue cooling, self-driving refrigerated transportation, and more. 5. Suitable for Lunch Bags: After receiving the ice brick pack, add water to activate. The ice crystal particles will expand after water absorption. Once expanded, freeze in the refrigerator for approximately 2–4 hours before use in lunch bags. Notice: 1. Actual color may be slightly different from the image due to different monitor and light effects. 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