These bottles are made from high grade poly propylene which means they are FREE from Bisphenol A. Our patented variable flow Non-Drip™ Nipple features anti-colic valves to reduce the risk of colic and teething nubs to massage baby’s gums. The nipple is uniquely designed so it is easy to use and prevents spills and leaks. No drips! No Spills! No mess! All smiles!