playtex ventaire advanced bottle with nip 3m+ 9 oz (2 pack) playtex bottom vent: unlike ordinary bottles that vent through the nipple, the ventaire micro-channel vents keep air at the back of the bottle as baby drinks, so virtually no air mixes with the milk and gets into baby's tummy. angled bottle: angled design promotes semi-upright feeding position recommended by pediatricians to help prevent ear infections. versatility: all nipple rings and caps are interchangeable with playtex nurser bottles for great flexibility. playtex selected the naturalatch nipple for all of our bottles because it mimics baby's latch-on like the breast. the natural nipple shape has a raised texture area that helps baby latch on naturally. leak-proof uniquely designed to reduce colic helps reduce air ingestion bpa free.