Compatible with all MAM Bottles, the MAM Slow Flow Size 1 Teats are suitable from birth and work with both breast milk and formula. MAM teats have a symmetric shape, which always fits perfectly in babies mouth. MAM Slow Flow Size 1 Teats have Skin Soft teat materia that feels completely familiar with a proud 94% acceptance rate and is designed with a symmetrically shaped teat, meaning they are always in the right position. Because babies grow quickly, MAM offer several different flow rates to perfectly suit whichever stage your baby is at. Teat 1 is the MAM slow flow teat which is suitable from birth or after Teat 0. Teats must be replaced every 1-2 months for safety and hygiene reasons.(Market research 2009-2017, tested with 1, 508 babies) Key features of MAM Slow Flow Size 1 Teats Suitable from birth Compatible with all MAM Bottles Works with both breast milk and formula BPA and BPS Free Skin Soft Teat feels so soft 94% of babies accept the MAM Teat