Lunavie Double Zip-Lock Breast Milk Storage Bag is a medical-grade sterilized double zip lock bag that is ready for immediate use. It is leakproof with double zip-locks to prevent splitting. It is made of BPA-free & non-toxic material. Lunavie Double Zip-Lock Breast Milk Storage Bag comes in different sizes designed in 5oz, 7oz & 10oz to maximize the mother’s requirement.