--- "Muzzles Keep a Good Dog Good." --- said a registered vet tech. Muzzles are a great idea to avoid biting and excessive barking when your dog is in stressful situations, including a vet exam and grooming session. It also prevents your dog from eating harmful leftover on the streets. Size: S-(Neck:4.7"; Mouth:6.7"-11.8"); S-(Neck:5.9"; Mouth:7"-11.8"); S-(Neck:6.7"; Mouth:7.5"-13.8")