Lansinoh breastmilk storage bags are pre sterilised and made from food safe polyethylene our manufacturing process enables us to produce these medical grade bags without using plasticisers so preventing substances which could be harmful to your baby from getting into your breastmilk featuring a double zipper for a secure seal and also a write on tab outside the fill area to eliminate potential puncture and milk contamination our storage bags are easy to write on even when full the bags c