Dr. Brown?s Natural Flow® is the only baby bottle to feature an internal vent system that: helps preserve vitamins C, A, & E by minimizing oxidation of breastmilk and formula provides positive-pressure vacuum-free feeding similar to breastfeeding; and helps reduce colic, spit-up, burping and gas by eliminating negative pressure and air bubbles.
I have never heard of these bottles or any of Dr. Brown's products. I noticed my daughter in law had many of this company's items on her registry. It is good to know their products are good and have great reviews. I will be looking to purchase some of these bottles for my new grandchild!!