Hygienic pre-sealing: The breast milk storage bag is hygienically sealed with durable materials and double zipper protection to prevent leakage. These bags allow breast milk to be safely stored in the freezer, refrigerator or while traveling.<br/> Durable Double Material - These breast milk storage bags are made with durable double material and a built-in double zipper seal to store breast milk safely in the fridge or freezer. Safe: Pre-sterilized, safe to store and BPA and BPS free. Designed to lie flat for quick freezing and thawing to protect valuable vitamins and nutrients in breast milk.<br/> Self-sharpening design: Our breast milk storage bags are self-contained and equipped with a large writing area, so you can record dates and other important information for safer storage and use.<br/> Ideal for breast milk storage: Our breast milk storage bags are ideal for storing, freezing and protecting precious breast milk. They are pre-sterilized and come with a double closure to prevent leaks.<br/> The breast milk storage bag is very sturdy and features a double zip seal to prevent leakage, and reinforced double seal side seams for maximum protection.