Just amazing! We hanged this at our little play gym and our baby at first was just hitting it a little, then more and more and now she would even grab it and put in her mouth. We got this when she was 1 month old and she could already see it and liked the noise it is making. Now at 2 months, if she’s at her swing and I would hit these toys in her gym, she would open her eyes as she recognizes the sound- absolutely cute, fun and developmental.See full review