High quality ovenproof borosilicate glass. Temperature resistant from -20 ° C? 400 ° C. Transparent lid with silicone seal. 100% airtight and waterproof. Cans close absolutely odorless. Lids are temperature resistant from -40 ° C? 200 ° C. Dishwasher safe. Oven and microwave safe (without lid) Suitable for refrigerator and freezer.