different for different types and sizes of bottles. Robust and flexible: flexible neck for easy cleaning in the bottom of the bottles. The brushes can be bent freely, you can always find a fit tool when cleaning gaps, dead corners. Material: plastic Easy to clean and store: You can clean it in the dishwasher. And they are easier to dry and easily stored in a kitchen cupboard or hung on a hook. Good cleaning helper: Each unique size and shape makes it easy to clean hard to reach places, such as teapots, wine decanters, coffee filters, pitchers, flasks, cups, tumblers, feeders, flower vases, kettle, straw, teapot and much more.