Putting the UnderDog on your canine friend is as easy as slipping it under the belly, attaching and cinching the two top buckles, attaching and cinching the neck collar, and adjusting the length strap between the dogs legs. The life jacket for dogs is the first ergonomically designed buoyancy aid for the swimming canine. with 90-Percent of the flotation in the water under the chest and neck, the underDOG supports the natural swim angle of the dog. Traditional dog vests pull the body into a horizontal position. With the underDOG the rear is allowed to sink lower than the forelegs, freeing the hind legs to swim more efficiently, while the neck is supported so that the head rides higher above the water line. It works with your dog so they are less fatigued after a long swim-they would tell you so if they could The split foam body has a mesh top to keep a dog cool. 2 body straps, a neck strap, and a chest strap can be adjusted. 2 grab handles provide even lift distribution, and are designed to support the full weight of a wet dog. The neck handle doubles as a handy leash attachment point. Generous reflective trim on the body and the neck provides added visibility when in the water or running around the parking lot. Tough CORDURA fabric protects the belly from rough ground cover. The underDOG sets a new standard for canine life jackets. SIZE: X-Small (2-12 lbs) Suggested size dog, Chihuahua, Papillion, Toy Poodle, Brussels Griffin, Havenese