Now there is a home fetal heartbeat monitor so you can listen to your baby's heartbeat at home. Just like the one at your doctor's office, you can keep track and know everything is ok, anytime you like. Use alone or use in conjunction with our fetal monitor belts (sold separately). If you are a healthcare professional, use this monitor in your clinic to monitor your patient's. There is also a twin monitor available. This product has a fetal heartbeat sound attached. The trigger is "fhb" without the quotes. It may not show up on your avi list. You have to type it in.