Super easy to use

I've used these liners since my daughter first came home from the hospital. We bought them originally because we liked the idea of less air and how that would mean less air in baby's tummy. However, now we love them for the convenience. They are SO easy! Once on vacation I had to use the traditional bottle and I hated having to wash them. I love just being able to toss in the trash after feeding my baby and then popping a new liner in the bottle when it's time for the next feeding. The liners are printed with the different increments in ounces and in milliliters so you can see when you are pouring liquid into the liner if you don't have it in a bottle at the time. Some of the older style Playtex bottles don't have all the ounce increments on them so this makes it easier to get a more exact measurement. Also, because you use the liners, you don't need the investment of buying a lot of bottles. This also saves you from having your counter tops taken over by bottles as they are drying, storage, etc. The liners are easy to find at Wal Mart, Target, Amazon, etc and most major grocery stores.

If the bottle is not very full, there is still a lot air in the liner that will still remain in the liner when the baby drinks the bottle. If the bottle is full, the liner collapses and the baby does not take in as much air as with a traditional bottle. If you are not feeding
your child a full bottle and you want your baby to get less air, once you have attached the nipple, you can GENTLY squeeze the sides of of the bottom of the liner and the excess air will escape out the nipple before feeding to baby. My only complaint is to see how much liquid is left in the bottle you have to unscrew the nipple to allow air back into the liner so it will return to it's normal shape so you can see the liquid and what ounce mark it is at. But that's really that big of a drawback. It is easy to push the air back out again to continue feeding baby.