"Show Pup" New Born Puppy/Kitten Identification Collars/Litter Bands (with Crystal Numbers) Take the guesswork out of identifying your puppies/kittens! Packs of 9 ID collars have removable Swarovski crystal numbers to increase your identification options Mix and match colors and numbers to track litters of 9 puppies/kittens or more Lightweight collars have traditional buckle closure for a secure fit Collar is 5/16" wide, fits neck from 5" to 7.5", use between 4 and 9 weeks of age, for small to medium breed puppies and kittens.