Review on 🐾 Kurgo Stowe Base Layer for Dogs - Dog Onesie Body Warmer, Bodysuit for Dogs, Recovery Suit to Reduce Anxiety & Shedding, Leash Opening, Reflective, Heather Black by Vanessa White

My mini aussie weighs 28 pounds. My Cavalier weighs 30 pounds. They wear a small or medium size depending on the Kurgo item. Medium length jackets. Small base layers. Small life jackets. My dog's back is about 17 inches on my Cavalier and 18 inches on my Mini Aussie. The length of the base layer corresponds to the length of the zipper. My dogs swam in the area. Small size is better for her. The hind legs are longer than the zipper so there are a few inches in there so the dog's back doesn't need to be less than 12 inches to fit in the little one. They are well made of thick fabric that stretches. The zipper is adjustable so one person can put the harness under the base layer and still attach a leash to it. They have reflective strips that work really well at night. They go well with a loft jacket. Haven't tried it underwater yet so can't comment on rain resistance yet. If in doubt about ordering it, just do it. Your dog can wear it alone or under a loft jacket for extra warmth. Kurgo is a great brand. If your gear breaks, their warranty policy is amazing. They really stand behind their products!