I had a smaller one that is for one person. This water flosser is perfect for all of my family. It came with 7 interchangeable nozzles and is sufficient for my wife and I and my kids. It has the 600ml large capacity that we can all use by a single fill. The range of speed from 30-125PSI is perfect for both us and kids and is gentle to the kid gums. You can have 10 different settings for your flossing experience. The best of all it is FDA approved. Professional done!!!