This is a simple, sleek design. Pour in a gallon of tap water, push a button. 3 hours later, you have a gallon of pure distilled water. And in the bottom of the still, you'll see all the gunk you won't be drinking. Just rinse it out. Ready to go again. Nothing really to go wrong, so these little stills run a lot of gallons. I've had a few over the last 30 years, running a gallon a day, and they really do the job.