The Joovy Boob Baby Bottle is the most innovative baby bottle on the market today. The new nipple design, patented CleanFlow Vent System, silicone sleeve, and bottle are state-of-the-art and use today's best design and materials. The PP Boob Baby Bottle has the same advanced system as our PPSU bottle but is made from PP (Polypropylene), a very durable plastic that is cost effective. It is available in clear, turquoise, and purple colors and is BPA, phthalate and lead free. Each bottle is individually shrink-wrapped to ensure the highest level of cleanliness. Our 1-piece CleanFlow vent is easy to clean. There is no assembly needed and no need to touch any part that comes in contact with the milk or formula. It provides consistent venting regardless of how the bottle is held. The vent's tabs fit perfectly into the bottle's neck to eliminate any miss-fittings that can cause leaks and inconsistent liquid flow. The nipples have been designed to make transitioning from breastfeeding to bottle-feeding and bottle-feeding to breastfeeding an easy and natural process. The large diameter base and nipple length assist your baby in properly "latching" onto the nipple. The Joovy PP Boob Bottle may cost more than others but the meticulous production process, material and quality are the absolute best available. There is no better bottle.