The OXO Tot Glass Baby Blocks are designed for portioning, storing, heating, and serving baby food. Made from durable borosilicate glass, these containers are thermal shock resistant, allowing them to transition directly from the freezer to the microwave or oven without shattering. The airtight and leak-proof SNAP lids ensure that food stays fresh and minimizes mess, making them perfect for on-the-go use. The stackable trays facilitate easy storage in your refrigerator or freezer, making meal prep and organization a breeze.