Glass food containers need to be tempered and resistant to extreme temperatures. Glass is the recommended container material when microwaving food. All of our glass containers are made from high quality and sustainable glass and are free of bpa, lead and other harmful toxins that can get into food. Our glazing and sealing materials are food grade and high quality, suitable for storing food. There is even a humane partition design. These glass food containers come from high quality and thickened containers to make them safe for microwave use. Our glass food containers are 400mL, 580mL, 600mL, 800mL, 860mL, 950mL, 1200mL, 1500mL. In addition, our glass food containers are easy to seal and leak proof.