I was quite surprised when I opened this package to find that this diffuser has to be run off of something with a USB port. I guess I could buy an adapter, but the cord is way too short to reach from where I wanted to put the diffuser to where the plug is. I purchased this diffuser for use in a meditation room that is in the process of being built. I admit I did not open the package as soon as it arrived. Unfortunately, by the time I opened the package and realized I can not just plug it into the wall, it was too late to be returned. Maybe my fault for not thoroughly researching how the plug works, but I have 4 diffusers in my home and NOT ONE of them has to have a USB port to work. VERY disappointed that this was a wasted purchase and I am out $25.00.
Fun! And cool. Great gift for my daughter. Only wish it lasted longer than 4 hours. Should make them bigger to hold more water. For those wondering, the light is optional.... can be turned off while still providing mist.