Leak-proof storage lids are for use with Mason jars while on the go and for food storage. Textured edges provide a comfortable and secure grip. Airtight, freezer safe, dishwasher safe, and BPA free. Not for preserving. The airtight seal is perfect for herbs, spices, on-the-go salads, smoothies, and more and is freezer-safe for storing jam recipes, sauces, and soups.