I wanted my baby 5 months and half begins gradually to take the bottle after exclusive breastfeeding until then, and after several successful trials with non Advent number 2 teats so that two holes, I bought these tétines- 4 hole there. I also tried several temperatures for milk and milk combination of several (one breast, breast milk over the first age, the first single age milk etc ...) and finally with these nipples then he ended up taking a bottle. I can not say that they are solely responsible but I can say that their speed suits him even with so much anti-regurgitation milk thickened. he is now 6 and a half months and he takes the bottle easily.