All collars are not created equal. And all dogs are different (some have more of a mane than others). Even though our collars are adjustable, it’s important to measure your dog's actual neck and not your old dog collar. The size of our collars are measured from the buckle bar to the holes and each hole is one inch apart. For example, the holes on the small sized collar are located 13", 14", 15", 16", and 17" from the buckle. Thus a dog with a 15" neck would likely fit into the third or center hole (15") of the small collar.
Remember that puppies grow quickly, so its important to check your collar often for a good fit. We recommend allowing a two-finger clearance between the collar and the dogs neck for a comfortable fit. You can measure your dog’s neck with a string, then measure the string with a flat ruler.