PRESSTOCLOSE TWISTTOOPEN PCTO Hasslefree handling with no spillage one handed closure Patent Pending PRECAUTIONARY DESIGN If the liquid in the bottle is too hot above 70 deg Celsius air pressure will force the fluid out from the sides This works as a precautionary in case the milk is too hot for consumption MORE NUTRIENTS LESS AIR Air venting bypasses the milk minimizing air bubbles oxidation of nutrients Builtin anticolic air vent reduces air intake MIMICS A MOTHERSS BREAST ellipticalshaped silicone teat simulate a latching experience making breast and bottle feeding combination possible Offcenter teat enables your baby to feed in natural upright position BPA BPS PVC PHTHALATES FREE created with FDA compliant and NSF certified PPSU that combines advantages of both glass and plastic material lightweight odor free Shatter resistant and Dishwasher safe top rack only STACKABLE EASY TO CLEAN softsquare design prevents the bottle from rolling away and allows it to be stackable to optimize storage REMINDER 5OZ BOTTLES COME WITH SLOW FLOW TEATS 8OZ BOTTLES COME WITH MEDIUM FLOW TEATS