Product Details:

Display: TFT Screen

Performance: FHR Value, FHR Mode, Volume Battery Status, Wave Form
Range&Accuracy: FHR Measurement Range: 50-210 bpm
Accuracy:±2bpm

Ultrasound Frequency: 2.5MHz

Dimension: 147.0x101.9×31.6(mm)

Net Weight: 250g±5g
Back light and Speaker: Backlight, Adjustable Volume

Battery Type: 1180 mah Lithium( Rechargeable) or AAAx3