RESEARCH ON BABY'S SUCKING BEHAVIOR: It is based on research on the 3 natural movements that a baby does while feeding in Japan. SOFT AND FLEXIBLE SILICONE NIPPLE: For seamless switch between breast and bottle. It’s super soft and flexible to allow for natural and smooth tongue movement. Latch-on Line: The new design with latching curve of the nipple is guiding for baby’s appropriate latch, so as to achieve effective adsorption. EASY TO USE: The new bottle shape features with wide neck and streamlined body, which is easy to clean and hold. SPECIFICATION: 8 oz (240 ml) bottle comes with M nipple (3 m+). Nipple size comes from SS to 3L with specific hole size shape, thickness and softness, different sizes for babies of every age. Recommended Age: 3 months+.