This 200ML COSSCCI Essential Oil Diffuser has three mist modes: High, Med and Low. It also has a timer with 4 settings. 1hr/2hr/3hr and continuous. I like keeping it on the low mist setting so it will run longer because I have this placed in the entrance way of my home and I have it on the continuous setting. I leave it on during the course of the day so when company comes the first thing they are greeted with is a nice fragrance. It depends on the mist setting on how long it can run without running out of the water. The higher the mist the less amount of time it will run. It can run up to 8 hours. This diffuser also has an automatic shut off when it runs out of the water. This is an important safety feature.
This comes with a wall outlet adapter that runs it. This is not cordless or battery operated. It has a 67 inch cord (5'feet 7" inches). Inside the machine water reservoir, it has a water line mark and should not be filled with water past that line. This comes with a manual on how to operate and take care of the diffuser properly. I have been using this for a month now and love it.