- Ultrasonic emitting frequency: 2.5MHz±3%

- Overall sensitivity at the 200 meters of distances: ≥90dB

- Effective area of the ultrasonic transducer active element: 1.57cm2

- Ultrasonic output power: ＜5mW/cm2

- FHR test range: 30 bpm ~240 bpm

- Battery type: 9V alkaline battery

- Ultrasound gel specification: density = 1.0g/cm2, speed ≤1.7m/s

- Acoustic impedance: ≤ 1.7x105g/cm2.s, attenuation ≤0.02db/mm

- Peak of negative acoustic pressure: p-<1MPa

- Output beam sound intensity: Iob＜20mW/cm2

- Ispta＜100mW/cm2

- Backlight turns on when there is fetal heart signal; Backlight turns into white light when the fetal heart rate is between 120~160bpm; Backlight turns into orange light and the fetal doppler sounds a warning when the fetal heart rate is less than 120bpm or more than 160bpm.

- No battery indicator shows in the lower right corner when the battery is at a high level; Batter indicator comes out when the battery is at a low level; When there is no cardiac value showing, but only battery indicator, then you need to replace the battery.

- In order to hear clearer, suggest not use headphones and speaker at the same time.

- Now you can safely listen to the prenatal sounds and monitor the heartbeat of your unborn baby in the comfort of your own home.

- Enjoy the amazing experience of hearing your baby's heartbeat, hiccups & kicks. Even record them to share with family & friends.