minbie has been successful in helping families avoid bottle refusal because our nipple allows your baby to feed with the same latch and feeding motion they use for breastfeeding. this kit contains 4 nipples in 2 different flow rates helping you match the right nipple to your baby’s natural feeding pace. the 6 nipples will help bub transition to a new faster feed rate with more control while the 6P nipple is anti-drip, requiring strong instinctive feeding (super helpful in preventing leaks when bub begins holding their own bottle.) the PPSU bottle in this kit is beautifully transparent like glass without the weight and worry of breakage and has a high heat resistance which is perfect for safe sterilisation. PPSU is completely free of BPAs, BPS, bisphenols, estrogenic and androgenic activity (EA free) so incredibly safe for your little one.