Our Closer to Nature bottle is inspired by what babies love most: mom. With the most breast-like nipple ever made, this bottle flexes like mom and feels like mom because babies prefer it that way. In fact, our Closer to Nature bottle has guaranteed acceptance and an anti-colic valve making it the best thing for baby since you, making feeding easier for everyone. Breast-like shape for a natural latch - acceptance guaranteed* * 92% of more than 1200 parents who used our nipple with their child recalled that they accepted it within the first 3 attempts. Flexes like mom for a comfortable feed, smooth silicone nipple feels closer to skin Anti-colic valve in nipple to reduce air ingestion Easy latch-on nipple - 97% mom recommended** **In a 2012 on-line survey of more than 500 moms who used Closer to Nature bottles, 97% agreed Always BPA and phthalate free for ultimate reassurance