The NutriChef NCGLBAB Glass Round Meal-Prep Containers are designed for convenient and efficient food storage. Made from high borosilicate glass, these containers can withstand temperature changes from freezer to oven, making them perfect for meal prep, leftovers, or storing ingredients. The airtight locking lids create a tight seal to keep your food fresh and leak-proof. These containers are microwave, oven, and freezer safe, and can be cleaned easily in the dishwasher. The stackable design helps organize your kitchen space, while the BPA-free lids provide added safety. This set of 12 containers ( 4.48 oz each) is perfect for portion control, meal prep, or taking lunch on the go.