Made from unbleached plant fiber, an annually renewable resource and good alternative to petroleum-based containers.Soak proof, freezer safe, and contain no wax or plastic lining.Great for grocery stores, supermarkets, restaurants, cafes, delis, and food trucks with takeout entrees, burgers, sandwiches and more.Gluten free.The tear drop shaped protuberances on the exterior of the clamshell containers are a trademark of World Centric.