Leerburg is proud to introduce the Keeper Collars Hidden Prong Collar. This is one of those products where design, quality, and functionality have all been taken into account. The Keeper Collars Hidden Prong Collar is not simply a cover for a prong collar. The prong is built directly into the collar, allowing for unmatched functionality and camouflaging of the prong. These collars are designed to easily be put on and taken off. Gone are the days of struggling to pinch the prongs together. For those people who do not have a ton of dexterity in their fingers, this is going to be a huge benefit. Sizing: Measure just under the jaw and behind the ears. The measurement should be snug but not tight. For example; if your dog measures 15.5" and is fully grown, a 14" collar would work because it fits a nice size that measures 14.5" to 16". Please refer to the sizing chart.