The Jumper Pocket Fetal Heart Doppler Ultrasound 3.0 MHz is a portable and handheld device designed for monitoring fetal heart rates and detecting potential abnormalities during pregnancy. With a probe frequency of 3 MHz, this Doppler is specifically catered towards obstetrics and gynecology applications, providing accurate readings for medical professionals and parents alike. The Jumper brand ensures quality and reliability in this important medical field, making it a valuable tool for detecting and diagnosing fetal heart issues. This thing works great! I was able to start hearing my daughter around 11 weeks with some searching. It was relieving to hear the heartbeat and know she was doing well.