- Add 2 inches when measuring your pet’s neck or chest to ensure a proper and comfortable fit. 2. Add 2 inches when measuring your pet’s neck or chest to ensure a proper and comfortable fit. 3. Dimensions are measured from the nylon tip to the outer edge of the buckle. Length measurements include the length of the buckle. 4. This necklace is more convenient to wear, lighter and more indispensable for going out