Perfect for my three month old baby. I had been using a medela calm, and when I switched to Nuk Size M 6-18m he was choking from excess flow. This S 6-18m teat has the ideal flow, and has no problem with the size (in my opinion it's the same 0-6 as 6-18, from what I understand, one is a little bigger than the other but the number of holes is the same). Used with two brands of formula (I'm mixed breastfeeding).
Anonymous A.