All babies deserve a healthy start. Reduce exposure to plastics and ensure purity with Lifefactory Glass Baby Bottles. Lifefactory Stage 2 silicone nipples offer medium flow allowing older 3 to 6-month old babies to transition as their appetites increase. Vented nipple design ensures reduced air intake to prevent colic and spit ups. These nipples are compatible with Lifefactory 4 and 9-ounce glass baby bottles. Made of the highest quality, thermal shock resistant borosilicate glass from France, Lifefactory bottles offer a healthy alternative to plastic bottle feeding. These bottles transition safely from freezer to boiling water while the silicone sleeve provides a tactile gripping surface for little hands and helps protect against the occasional drop. Lifefactory Glass Bottles grow with your baby--they can be used with the range of Lifefactory nipples, sippy caps and leakproof flat caps--providing years of use. While very durable, Lifefactory bottles are still glass and are not unbreakable. Replacement bottles are available. All Lifefactory bottle components are made in the U.S. or Europe. All materials are BPA/BPS-free and phthalate-free.