- The SD3 series ultrasound Doppler is ideal for routine fetal heart rate detection. 

- The SD3 Pro is designed for intermittent fetal sound auscultation.

 - The 2 or 3 MHz water-resistant probes can be used for fetal heart rate detection as a general indication of fetal well-being and also to check fetal heart viability after patient trauma. 

- Built-in rechargeable Li-ion battery 

- Compatible with AA batteries 4/5/8MHz probe