The Classic Winged Nipple is a soft winged nipple for less gas and fussiness. The winged shape helps fit the corners of baby s mouth which reduces air intake and helps keep milk in. Micro Air Vents help to prevent or reduce nipple collapse by balancing air in the bottle. The nipples are made of soft flexible silicone and are BPA Free. From the Manufacturer The Classic Winged Nipple is a soft winged nipple for less gas and fussiness. The winged shape helps fit the corners of baby s mouth which reduces air intake and helps keep milk in. Micro Air Vents help to prevent or reduce nipple collapse by balancing air in the bottle. The nipples are made of soft flexible silicone and are BPA-Free.