Comotomo Baby Bottles feature innovative and sensible design to most closely mimic natural breastfeeding. Our naturally shaped, soft, silicone nipples are ideal for babies who have trouble transitioning from nursing to bottle-feeding. Your little one will love to hold onto the skin-like, soft and squeezable body that is like no other bottle in the world. And you will fall in love with our wide-neck design for brushless, stress-free, cleaning bliss! Our bottles are equipped with truly innovative vents that are smartly designed to prevent colic, while completely eliminating annoying leaks. They are quite possibly the most thoughtful bottles ever made. (Please note: 5oz bottles come with a truly slow flow nipple suitable for newborns upto 3 months. 8oz bottles come with medium flow nipple suitable for 3-6 months).