I use this to help my 2 year old sleep through the night. He is a light sleeper and we live on a main road. With this sound machine, my 2 year old is sleeping better through the night. I keep the machine on all night but there is also an optional sleep timer. I love how compact it is and that I have the option of using an ac adaptor or batteries. There is 6 sound choices. I prefer to use either ocean or summer nights. [This review was collected as part of a promotion.]