Like humans, some dogs are better swimmers than others. And like all swimmers, they will eventually tire. Even a good swimmer might be disoriented from the shock of falling in the water. Most pet life jackets are designed to keep the animal in a horizontal swimming position. The UnderDOG is different. By moving 90% of the effective buoyancy under the chest and neck, the vest is designed to allow a more natural swim angle with the hind legs lower than the front.
| Size |
Weight |
| XS |
2-12 lbs |
| S |
12-24 lbs |
| M |
24-60 lbs |
| L |
60-90 lbs |
| XL |
90-120 lbs |
