Lunch bags are generally used for picnics. A regular bag cannot hold food, it is prone to odors and spoilage. But the lunch bag is different. It has a special preservation and constant temperature function, which can ensure that the food is warm in winter and can be used as a small refrigerator to carry cold drinks in summer. Because it is a bag for storing food, its material is very resistant to dirt and easy to clean. Whether it's a family gathering or a friend going out for a picnic, a lunch bag can bring you great convenience and solve many troubles.