These breastmilk storage bags are a must for any pumping mom! I was already using the Lansinoh storage bags when I purchased this product but I needed the pump adaptors that come included in order to pump directly from my Medela breast pump. The bags themselves are great. They are thick, leak proof, and have a double seal to ensure none of your liquid gold is lost accidentally. The pump adaptors just sweeten the deal by making it more convenient to pump without having to use a bottle to pump into and therefore saving you from wasting time transferring your milk and having more dishes to wash.