Microwave Safe, Oven Safe- can be used as a baking dish, Freezer Safe, Dishwasher Safe Air-tight, Leakproof Containers – You can use them for Storing, Reheating, Baking and Serving, made from high quality borosilicate glass- non toxic, no odour and stainproof Smart Locking Lids with Air- Vents (LIDS ARE NOT MICROWAVE, OVEN or DISHWASHER SAFE) gives ease in reheating or storing hot food as air vents let the vapours out and keeps food fresh.