Ultrasonic Dot Pattern Waterproof Ice Pack for Lunch Box is manufactured using advanced ultrasonic technology, which ensures a strong bond between materials and prevents moisture penetration, providing reliable freshness preservation for your lunch. The exquisitely designed dot pattern not only adds fashion to the product, but also improves its durability and waterproof performance. You can safely place this cooler bag in your lunch box without worrying about moisture leakage, ensuring your food stays fresh and chilled. Whether in the office, school or traveling, this cooler bag is your ideal companion. Our specially designed size and construction allow it to fit perfectly into most lunch boxes, providing optimal holding space and freshness retention. The lightweight and portable design allows you to take it with you and enjoy a fresh and delicious lunch at any time.