These are the original puppy litter collars sold by Puppies in Bloom providing a colorful and easy way to identify each puppy in a litter. Our Puppy ID Bands come with 12 bands (collars) in assorted colors. Each puppy will wear a different color for unique identification from litter mates. The bands wrap around and self-attach. No buckles, fasteners or string. The material has a secure grip, but is lightweight, thin and soft enough for newborns. Easy to adjust as the pups grow. Three sizes to choose from. Designed to use with our color coordinated PUPPIES IN BLOOM Record Keeping Charts, sold separately. The charts can be found by searching for ASIN No. B00IQFN9ZO on Amazon.