Insulated and Leak-Proof Picnic Bag An insulated and leak-proof picnic bag is a practical essential for outdoor picnics. Its outer layer is usually made of water-resistant and wear-resistant fabrics, such as PVC-coated cloth or TPU material, paired with waterproof zippers to effectively prevent rainwater or drinks from seeping in. The interior features an insulation layer, mostly composed of food-grade aluminum foil, honeycomb insulation cotton, or pearl cotton, which can keep food hot or cold for an extended period. Some picnic bags also have large capacity and multiple compartments, facilitating classified storage of food and tableware to avoid flavor mixing. Additionally, certain styles are designed with double shoulder straps for easy carrying. Whether it's a family gathering, a couples' date, or a friends' outing, it allows you to enjoy a delicious picnic time effortlessly.