KRY Glass Lunch Boxes are made of all things healthy, stylish, and aesthetically pleasing. While the bowls are made from 100% Food Grade durable Borosilicate glass, the covers are made of BPA-free virgin plastic. The air-tight containers keep your food and beverages fresh for longer hours. The spill-proof containers are easy to clean and maintain, ensuring zero mess. KRY glass material makes the Signora ware lunch boxes sturdy and durable. Borosilicate glass has excellent thermal qualities and remains shatter-proof even at sudden temperature changes.