I used this at home several times. We could hear the fetal heartbeat, and my family and I enjoyed the pregnancy period. The box is missing. Even without the dedicated gel, I could hear the heartbeat well with a gel-like cream. There is no instruction manual, but the usage instructions are available online. Please understand that this is a used item. It has been tested and confirmed to be working. *The main unit is a medical device, so this is an offering of the accessories. Please comment if you have any questions.