Classic style halter (classic because it connects to the lead under the dog's jaw) and has been the Halter of choice for many trainers for the past several years. The dynamic design allows the Halter to move as the dog moves, leaving the nose bridge strap to sit comfortably in the same position. This means it doesn't tend to ride up close to the dog's eyes and the dog is more content while wearing the Halter. Sizes: Mini: Adjustable to fit neck from 20 to 35cm. Small: Adjustable to fit neck from 27 to 37cm. Medium: Adjustable to fit neck from 35 to 52cm. Large: Adjustable to fit neck from 43 to 68cm. XLarge: Adjustable to fit neck from 58 to 94cm How to get the best fit for your dog: The Noseband and Cords on the Training Halter allow for a large adjustment, so sizing is based on a dog's neck measurement Use a soft tape measure place it around your dog's neck up close behind the ears, this is where the neck strap should fit and take a snug to tight neck measurement. Check your dog's neck measurement against the list above, to select the appropriate size. Important: If your dog fits between 2 sizes, generally select the smaller size, UNLESS you are fitting a growing dog in which case you might go for the larger size to allow for future growth.