I prepare alot of food in advance,and these glass storage containers are the best. They go from freezer to oven or microwave for reheating, and right onto the table. Eco-friendly because they are glass rather than plastic, and dishwasher safe. They stack well in the freezer or fridge, and are just perfect for those meals which need to be delivered to folks who are food deprived. Will never use anything but Pyrex@