The Chuckit! Hydroroller is perfect for pools, lakes and beach play. The internal reservoir is designed to hold water and spray when thrown or rolled for games of ground pursuit fetch. The added play dynamic of water helps keep dogs cool in warm spring and summer weather. Submerge the Hydroroller in water to easily fill the reservoir. Bright blue and orange color provides high-visibility on land. Made from durable rubber and available in one size that is suitable for most dogs.