Our Options ™ bottle in pharmaceutical-grade borosilicate glass. Durable glass withstands hot, cold, and gradual temperature changes. The soft silicone nipple helps baby naturally latch while the anti-colic vent system lets baby feed without fuss. Together, they offer a reliable and trusted bottle-feeding experience that makes Dr. Brown’s the #1 pediatrician recommended bottle in the U.S and a favorite of parents for over 20 years.