Adiri NxGenTM is the next generation of infant nurser. Designed with advice from practitioners, scientists, lactation consultants, cutting edge designers, engineers and most importantly moms. Adiri NxGenTM delivers the most efficient bottle feeding system available. </br>Features: </br>Bottom vented, one-way petal valve offers consistent air flow reducing possibility of colic. Supports transition from mother's breast to bottle. Soft medical grade silicone nipple that is ideal in shape and size; Bottle disassembles in 3 convenient pieces for ease of cleaning. Dishwasher safe (top rack only); BPA free. Designed for 6-9 months of age; Medium flow; 4 pack.