ADJUSTABLE SIZE: 18pcs/set, come with 18 different colors, easy identification. Fits 7.5 to 12.5inch neck size, collar is 2/5 inches wide.GREAT MATERIAL: Made of lightweight and flexible nylon fabric material, the kitty identification collars is soft and lightweight, which put little pressure around the cats neck; Very comfortable for your cat to wear and can fit most pets.TARGET AUDIENCE: Great for puppies from birth to 8 weeks old, also can be used for cat, kitten or other small animals whose neck girth is within this size can wear.SAFETY BUCKLE: Our puppy ID collar has a safety quick buckle. When a certain pressure is applied, The breakaway safe buckle will release and fall off, which is very safe for your puppy.REFLECTIVE STRIP: There have reflective strips and tiny bells on each collar, make it easy to keep up with the pups in the dark.