Measurement #A – Head & Ears Measure the largest part of your dog’s head, which includes the ears. This allows the collar to slip over the dog’s head comfortably. Measurement #B – Behind the ears Measure the smallest part of the dog’s neck, which is right behind the ears. If your dog has a thick coat, be sure to pull the tape measure or string through the coat and measure right behind the ears. Measurement #C – Mid-Neck Measure the mid-neck of your dog (the point where you prefer the collar to rest on the neck) using a cloth measuring tape. If you do not have a cloth tape measure, use a piece of string and then measure the string. Pull the tape or string up to your dogs mid-neck with no slack. If your dog has a thick coat, be sure to pull the tape measure or string through the coat and to the base of your dog’s mid-neck. If your dog has loose neck skin, be sure to pull the tape measure or string through the loose skin slightly.