Package included: 1x Household Prenatal Baby Beat Monitor 1xBattery 1x couplant Specification: Product name: Pocket Fetal Doppler Prenatal Baby Beat Rate Detector Material: ABS plastic Size: 8cm*3cm*12cm/3.1*1.2*4.7inch Weight: approx.300g Screen size: 1.8 inches Voltage: DC 3V Battery: 2pcs AA battery(not included) Probe operating frequency: 2.0MHz±10% Fetal heart rate range: 50-240 BPM (per minute) Maximum output sensitivity: 2100Db Ultrasonic output intensity: