Innovative 4-ounce (120 ml) glass baby bottle with protective silicone sleeve, Stage 1 silicone nipple for newborn infants from 0 to 3-months and polypropylene (PP#5) cap, ring and stopper;Thermal shock resistant borosilicate glass bottle transitions safely from freezer to boiling water; all components are dishwasher safe; sleeve and bottle can be washed/sterilized together;Protective medical-grade silicone sleeve provides a tactile non-slip gripping surface and helps prevent breakage;Bottle grows with baby--use with Lifefactory stage 1, 2, 3 and Y-cut nipples, sippy caps and leakproof flat caps ; compatible with most major breast pumps;Healthy alternative to plastic bottle feeding--all components are made in the U.S. or Europe and are BPA/BPS-free and phthalate-free