These are fantastic. I keep one in my car and have one at home, and another in the dog stuff go-bag. They fit on pretty much any plastic soda or fizzy water bottle, and are great for rinsing a dog off before they get in the car, helping to clean a dog off after tummy trouble when a bath/hose isn't available, or gently (and more diffusely than just pouring) wetting a dog to help keep them cool. I also use them to dilute and apply shampoo when bathing dogs. It can be tricky finding the right bottle for your needs, I have large hands for a woman, and use the large plastic Pellegrino fizzy water bottles. I can squeeze firmly and get decent water pressure, and the bottles spring back into shape. When they start to perma-dent I either swap them out or blow into the bottle to re-inflate. This is a really nifty gadget to have on hand, and one of my go-to gifts for dog club holiday gifts and new puppy baskets.