M SIZE - DESIGNED FOR MEDIUM SMALL DOGS: Fits chest 16.1-18.9 inches | Upgraded 0.8-inch webbing (better load-bearing) + 59-inch leash, great for Pugs, Boston Terriers, 4-6mo Corgi puppies, 3-5mo French Bulldog puppies (larger small breeds) – measure chest carefully; size up if your dog is between sizes for optimal comfort.
