Feature:1. FITTING CURVE: According to the ergonomic design, fully conforms to the belly curve, using 3D fitting technology, fitting curve.2. FETAL EDUCATION COMFORT: Fetal education music, heart sound, fetal education comfort, light fetal education, parent child dialog to meet the comprehensive needs of fetal education.3. EARLY LANGUAGE DEVELOPMENT: Children grow fast, musical sense, strong adaptability, excellent character, has been strong, developed right brain, early language development.4. BELLY POCKET: The product also has a belly pocket, which can wear the fetal education instrument directly on the stomach, and listen to it anytime and anywhere, which is very convenient.5. VOLUME CONTROL: Volume control helps your baby get to sleep without keeping everyone else awake. The device is one of the essential crib accessories to ensure a quiet house for the whole family.Specification:Item Type: Prenatal education music machineMaterial: ABSRated voltage: 3.7V Storage capacity: 8-16G Illumination Range: About 570mm / 22.4in yellow light Speaker Sound: About 50-60dB Volume Adjustment: Default volume (within 2000HZ) Functions: Monthly fetal education, spectrum assisted fetal education, parent child dialog, dual listening headphones, music machine. Size: Approx. 170 x 70 x 30mm / 6.7 x 2.8 x 1.2inFull Time: 3.5 hour Continuous Working Time: 6-8 hourBattery Capacity: 1000mAh(built in) Sound Output: Speaker, cable Speaker: non magnetic built in Music Format: WMA, MP3 dual download mode Range: Between 20 weeks and 3 years old How to Use:1. long press the power button for 3 seconds, the machine will start, the music will automatically refer to the content of the first folder, and press the pause button for 1 second. 2. light switch, the light is a separate switch after starting, long press 1 second