Most muzzles have a strap made up of two pieces that go behind the ears. These straps connect behind the ears on the back of the neck with a buckle. We sell an accessory kit that allows the owner to remove the buckle and use a quick-release snap buckle.
The second style muzzle has a third strap that in addition to the straps behind the ears, the third strap goes between the ears. Police K9 dogs use this style of strap. Most (not all) pet dog owners do not need a three-strap muzzle. The deciding factor would be if the dog has serious aggression issues or needs a more snug fit.