Question about Medela Calma Breast Teat

Ha, comes incl. protective cover. Super sour, same size for the whole bottle time with mu milk. But baby has to practice a bit - as with breastfeeding - because the milk doesn't just run out like with other teats. But they take the breast longer

It has a plug-in cover at the top and a twist-on lid at the bottom that also fits on the bottles. Everything can be sterilised.