I started using this when with my then 6 month old who was only breastfed and my flow is fast so he gets impatient. He never took to a bottle. The original teat on this Sippy cup he didn’t like but once I changed it to this teat, he loves it. Took a few weeks to adjust to learning how to stop and swallow and not drip everywhere but now he is a pro! And he drinks expressed breast milk sitting on his high chair . I feel so relieved! We are also introducing powdered milk now he is turning 8 months old and he’s taken a few sips from it today. Highly recommend this weighted straw Sippy cup and extra teat.