Natural nipple helps combine breast and bottle feeding, Comfort petals make nipple softer and more flexible, Nipple shape promotes natural suckling motions, Twin anti colic valves make feeding more comfortable, Durable silicone is odorless and easy to sterilize, BPA-Free and made of soft, durable, flavorless silicone, Wide, breast-shaped nipple promotes natural latch-on and makes it easier for baby to combine breastfeeding and bottle feeding, Comfort petals make nipple softer and more flexible to prevent nipple collapse, Innovative twin valve design reduces colic and discomfort, Includes 2 Natural Fast Flow Nipples