Durable material and leakproof design: Crafted with construction, the ice packs for coolers use a thickened PE material that ensures leakproof performance and is easy to clean for lasting use in various settings. Strong cold storage capacity: This ice crystal box contains dry ice crystal particles, which are relatively coarse, have good expansion properties, strong cold storage properties, large capacity and energy storage, enabling long cooling cycles. Easy and convenient to use: The reusable ice pack can be placed in the freezer for approximately 24 hours and can be removed for use in lunch bags, etc. Do not up when adding water, as ice crystals will absorb water, expand and freeze. Cold and frosty performance: The home freezer blocks can be used as ice crystals for air conditioning fans, cooling the air conditioning fans and making the cold air even cooler. Includes 8 reusable ice packs, which can improve air cooler efficiency and deliver prolonged cooling retention. Practical applications Keep foods and beverages cold during picnics, road trips, camping, and use in lunch bags or coolers. Enhance cooling in small home or office setups by use with air conditioning fans for cooler air. Suitable for outdoor events and other settings where longlasting, reliable cooling is needed.