Long-lasting cooling: Reusable ice crystal boxes keep lunches, drinks, and snacks cold for hours, helping maintain food quality and prevent spoilage during work, school, fishing, camping, or road trips. Durable and leakproof construction: Made from premium, leakproof materials for safe, contamination-free cooling. Designed to withstand repeated use in lunch bags, picnic baskets, travel coolers, and as extra cooling blocks for portable air conditioners. Multi-purpose cooling solution: Use for school lunches, outdoor activities, beach or picnic outings, travel, and temperature-sensitive items such as dairy or medications. Reliable cooling for drinks, fruit, sandwiches, or medical supplies when refrigeration is not available. Compact and travel-friendly design: Lightweight and slim profile fits easily into cooler bags, lunch boxes, backpacks, and portable air conditioners without taking up excess space — convenient for commuters, students, and outdoor enthusiasts. Practical use scenarios School or work lunch: Place an ice crystal box inside a lunch bag or box to keep sandwiches and beverages chilled until mealtime. Outdoor trip or camping: Stack with ice or place among food containers in a cooler to extend cold retention on day hikes, fishing trips, or weekend camping. Travel and portable AC support: Use inside travel coolers or as supplemental cooling blocks for portable air conditioners to boost cooling performance on long drives or in small spaces. Key attributes Function: Reusable cold pack for preserving temperature-sensitive items Compatibility: Fits lunch boxes, cooler bags, travel coolers, picnic baskets, backpacks, and portable air conditioners Performance: Keeps contents cold for hours with repeated use Design: Slim, lightweight, and easy to pack Safety: Constructed from premium, leakproof materials for safe, reusable cooling