I have been putting off writing a review so I could give this item the fairest chance of proving itself, if you like. If you think you will buy this product and hear your unborn babies heartbeat as soon as you use it, you wont. What you will most likely hear is tummy gurgling and various internal noises but if you are persistent you will hear occasional kicks and punches. I cant even describe what it sounds like but you will know what it is because it sounds so strong in comparison to any other noise. The later on in pregnancy you may hear the hearbeat but you can easily mistake it for your own if you are too desperate to hear the baby. I did this at 16 weeks or so and was very disapointed when I realised my mistake.
This product only enables you to listen to your baby moving around inside your tummy, it is not like a fetal doppler the midwife uses so lower your expectations if you are going to buy one. If you do purchase it I would strongly recommend you change the headphones for better ones. This is what I did and I now get alot of enjoyment from sitting quietly still and hearing the baby move. I hope to hear more sounds, maybe a heartbeat thats not mine the further along I get but even if it stays the way it is and I only hear the 'doinks' of a punch or kick, i'm happy with that.
Overall not worth £20 in my honest opinion but second hand on an auction site, definately.