Features: Insulated and Leakproof Function : Crafted with a polyester fabric exterior , aluminum foil lining , and foam insulation , this food delivery backpack keeps food hot or cold for longer periods . The waterproof zipper helps avoid rain from soaking the food inside. Sturdy Internal Support for Stability : Equipped with a back support board and 2 detachable side support boards , the insulated pizza delivery backpack maintains structural stability. Expandable Storage Space : The food delivery backpack features a spacious interior with expandable pocket , which can hold utensils , napkins , additional containers , food carrying bags and other items. Enhanced Safety : Reflective strips on the food delivery backpack improve visibility during nighttime or low light conditions , providing extra safety for users , hot food carriers , and pizza picnic bags. Versatile Use : This food delivery backpack keeps food fresh during food delivery , picnics , hiking , barbecues , outdoor activities , and more , making it ideal for the takeout and catering industries. Size : 40x27x35cm/15.75x10.63x13.78inch. Material : Oxford Cloth + Pearl Cotton + Aluminum Foil