I always wanted to get this product even though I read all review and this product has a poor review but I believed those couple people who gave good reviews. Do not buy this product. I bought this product when I was 4.5 months pregnant. My husband and I tried this product and follow the instruction almost everyday for 2 weeks. You cannot hear the fetal's heartbeat but everything else. You can't hear your own hearteat when you put it against your chest. I was going to keep it for the Microphone but by 6 months my baby can hear everything outside the womb. I can just play the music from the CD player and the baby can hear it. So we returned the product. Please don't buy this product just keep your money for those Baby Mozart and other classical music CDs.