This water bottle is truly a godsend! I cannot imagine using any other travel water bottle for my pups! It is slim, fits perfectly in a bottle slot in my travel bag; it is lightweight and has a loop to put around my wrist when I walk with my pups. It is extremely convenient on car rides, when my pup is thirsty and needs a quick pick-me-up! I especially love the fact that it sucks the water back in, so that I am not wasting unused water. The 12oz bottle is perfect for tiny dogs. Anything bigger than 10 lbs, I would recommend you purchase the larger bottle.