1、22 KINDS OF SLEEP SOUNDS: Sleep sound speaker has white noise, running water, birds, frogs, insects, trains, thunder, clock walking sound and so on 22 kinds of sleep sounds to help you fall asleep quickly.2、TIMER FUNCTION: Sleep sound machine has a timer function, you can set it to play continuously or set the timer 30, 60, 90 minutes to turn off automatically.3、ADJUSTABLE VOLUME: Sleep machine volume can be adjusted, it can cover up the surrounding noisy environment sound, do not worry about being woken up by the noise.4、SUITABLE FOR THE CROWD: White noise machine this special gift with great love, will give you the most peace of mind sleep, suitable for babies, children and adults.5、EXCELLENT GIFT: White noise sound machine is suitable for home, office or when traveling, it is a gift for Valentine's Day, Mother's Day, Father's Day, Christmas, New Year and birthday.