[Built-in sound] : built-in 14 sounds (10 natural sounds: crickets, streams, seagulls, thunder, birds, birds, waves, rain thunder, baby birds, rain ticking, 1 train, 1 fan sound, 2 white noise) [Timing function] : The ON/OFF position of the ON/ Off key is available for 60 minutes and 120 minutes respectively. The default mode is long-term playback [Bluetooth function] : Long press the Bluetooth key "Bluetooth", the voice prompts to switch to Bluetooth mode, and then open the Bluetooth connection of the mobile phone, select white noise 01 available devices, you can connect successfully. Long press the Pause key "Pause" to exit and then switch to white noise mode [Night light function] : Two modes of warm light and bright light can be adjusted [Battery] : Built-in 2500mAh lithium battery, when the power is low, there will be a prompt tone [Battery life] : The charging time is about 4h, and the use time after full charge is about 6-7h