Best One I've Used

I love this.   I usually sleep with a small box fan running but they wear out quickly for some reason and I keep having to replace them.  I have used other sound machines but none have been able to duplicate a fan in a way that I am able to go to sleep to except this one.  It has different settings but so far the only one I have used is the one that sounds to me like a fan running.  You can set a time limit on it if you want to and you can adjust the volume.  I have used it every night since I received it.