S(Snout Cir 7.5-9"): The small dog muzzle is ideal for Corgi and so on(reference only), but not suitable for aggressive, over-active and flat-faced dogs such as Shih Tzu, Bulldog, etc Measure Tips: Don't choose a size based on breed, weight, or previous size. Your dog's snout circumference should fall within the size chart when you're choosing, and most importantly your dog's snout length must be greater than the value in the size chart you purchased Adjustable Hook & Loop: This soft dog muzzle features an adjustable hook & loop around the snout that allows you to adjust a comfortable fit for your dog. Our mesh dog muzzle with a release buckle is easy to put on and remove Vision-Friendly Safe Muzzle: The width of the hook & loop part is specifically designed to cover the snout without blocking your dogs vision, allowing your dog to be active as usual. Ideal for dogs who are sensitive to traditional muzzles Comfort & Durability: Prioritizing your dog's comfort, our soft muzzle for medium sized dog is lightweight and breathable with air mesh. The mesh muzzle for dogs also features a soft-edged design that ensures a gentle feel against your dogs skin Safe Bite Control: Our dog mouth guard is effective for biting, and chewing during walking or training. Since it is a soft muzzle, the dog muzzles to prevent biting is ideal for anxious dogs in grooming, Vet visits, trimming nails, or meeting strangers