The hoof gauge is used for measuring the angle of the hoof bottom to the front wall. Used by professional farriers and veterinarians, hoof gauges are valuable farrier tools and veterinary supplies. This particular model is our best seller primarily because of its price point, and it fits the average sized hoof. The measuring diagram on the side is a nice point on a clearly marked measuring surface. The Brass horse hoof gauge is a popular item in farrier supplies. Anvil Brand horseshoeing supplies best seller item.