Harmany Muzzles Grazing Muzzle Humane. The muzzle offers 50% more breathing room than traditional muzzles Customizable. Form to your horse's head shape and dictate the amount of grass available. Durable. Kevlar fibers make it tough and long-lasting. Attaches to any breakaway halter with heavy duty velcro straps (included). Available in four sizes: mini, pony, horse, draft