MTI made the UnderDog Personal Flotation Device to provide flotation without interfering your dog's natural swim angle. Most of the effective buoyancy is under the neck and chest to ensure proper dog-paddling mobility. The cool mesh on the back and shoulder area also add some stretch for freedom of movement. There are four adjustable points that ensure a secure fit. MTI added reflective paneling and bright webbing at the carry handle and leash attachment to increase visibility. Except for the mesh panels, the entire exterior is made out of Ballistic nylon for long-lasting durability.