What is a cooler lunch bag ? Cooler lunch bag is to store cold food or cold drinks,helps food maintain its temperature and not be melted. Top closure. It is handy to carry and it is made of durable, easy-clean polyester fabric, with leak-proof interior lining.Cooler lunch bag can be used to store refrigerated food when you are going out and keep your cold items at a good temperature from the store to your home and not worry about everything going bad. In hot summer, the cooler lunch bag brings convenience to many young people who bring meals to work. The material used is light, easy to carry, and easy to clean, and most cooler lunch bags are sturdy, reusable, washable, and low cost to use.