Buster muzzles. These metal dog muzzles are robust with a strong leather strap to keep your dog secure. The muzzle nose rest is made up of felt material for added comfort.. Size 5 suitable for dog breeds such as beagle, border collie, cocker spaniel, poodle, welsh terrier.. Size 6 suitable for dog breeds such as dalmatian, elkhound, german shepherd, pointer, springer spaniel.. Size 7 suitable for dog breeds such as english setter, flat coated retriever, foxhound, golden retriever.. Size 8 suitable for dog breeds such as gordon setter, english setter, german shepherd, old english sheepdog, weimaraner.. Size 9 suitable for dog breeds such as irish wolfhound, afghan hound, bouvier, great dane.. Size 10 suitable for dog breeds such as large irish wolfhound, large afghan hound, large bouvier, large great dane.