NOTICE:Not absolutely,your smart dog can also get rid of muzzle,please use it with a collar.
5 SIZES: 5 different sizes in each set,made from strong nylon fabric with a fully adjustable strap and fasteners for an easy fit.
MATERIAL:Waterproof Oxford cloth, light and breathable, Adjustable strap with release buckle, Soft Lightweight and Durable, Skin-friendly to dogs and easy to put on.
BREATHABLE & SECURE & EATABLE: Waterproof Oxford cloth, it is breathable when putting on, and it also allows the dog to open his mouth enough to eat/drink/pant, but still prevents biting to stay secure.
ABOUT SIZE: Pleason note that this muzzle is designed for dog with long snout, Please measure your dog's snout to ensure this is the correct muzzle size you need(check the size map from the picture to get more detail).