1、ADVANCED SOUND TECHNOLOGY: White noise machine utilizes advanced sound technology to highly reproduce white noise, providing a more comfortable sleep environment and making it easier for your baby to fall asleep. 2、BUILT IN 20 SOUND SOURCES: There are 20 built in sound sources, including white noise, nature sounds, and fetal sounds, to meet different baby's sleep needs, and there is no need to connect to download to use it. 3、CONVENIENT: White noise machine is ready to use when you turn it on, no need to connect to wifi to set up the network, convenient and fast. Lightweight and portable, you can use it anytime and anywhere. 4、LOW BATTERY ALARM FUNCTION: When the speaker's battery is low, the device will emit a drip drip drip alarm to remind users to recharge in time to avoid interrupting baby's sleep. 5、TIMER FUNCTION: White noise sound machine supports timer function, users can set the playback duration according to their needs, the timer parameters are categorized into 30 minutes, 60 minutes, 90 minutes and off. 1 x Portable White Noise Machine1 x Data Cable1 x Instruction Manual Item Type: Portable White Noise MachineMaterial: ABSSound Source: 20 Kinds Of Sound Source (5 Kinds Of White Noise, 14 Kinds Of Natural Sound, 1 Fetal Sound)Frequency: 60-20KHZSignal To Noise Ratio: >75dBDistortion: ≤1% (1W,1KHz)Speaker Specifications: 40mm 2Ω 3WSound Format: WAVBattery Type: Built In 1000mAh Lithium Ion BatteryUsage Hours: 9 Hours (Medium Volume, Night Light In The Light), 14 Hours (Medium Volume, Night Light Off) (Test Sound Source: Antique Fan)