Tested and working A system to encourage learning in unborn babies through sound. - Brand: babyplus - Product Name: babyplus Prenatal Education System - Included: Instruction manual (Japanese) - Features: A system to encourage learning in unborn babies through sound. Batteries are not included. Also, I think this is true for all of these products, but the batteries seem to drain quite quickly. I changed them about three times from early pregnancy. There are no operational issues. This is just my personal opinion, but I used this product and gave birth to a child who cried less at night, making them easier to raise. This is just my subjective experience, so please take it as a reference. Thank you for looking.