Dog Life Jackets (or dog life vests) make a big difference for your water loving furry friend when they are in the water. Dog life vests are designed to aid your dogs bouyancy when in the water. The "Pup-Guard" dog life vest from Travelin K9 does this better than most other models with the additional neoprene designed into the body tabs on the life jacket. This added neoprene adds significant additional flotation which allows your dog to stay afloat with less effort than most other models on the market. Even young dogs can quickly wear themselves out in the water as they try to keep their head above water. The "Pup-Guard" dog life vest, with its extra neoprene design, will allow your dog to "doggy-paddle" with much less effort. In addition, the padded, reinforced handle makes it super easy to lift your dog up onto the dock, or your boats platform/ramp. A convenient "D" ring allows for a leash, waterproof light or whatever you want to attach to your dogs life jacket, while the high visibility red neoprene with reflective strips allow you to keep an eye on your water loving pet. Body Girth is the most important measurement of the 3 dimensions. EXAMPLE: 19" chest girth would be best suited for a Medium Size Life Vest.