SMALL: 17.8cm - 26cm neck, MEDIUM: 21.6cm - 34cm neck. Width: 1 cm. 14 pcs/set, comes with 14 different colors for easy identification. Designed for puppies from birth to 10 weeks old. Can also be used for cats, kittens, bunnies, guinea pigs, and other small animals. Made of soft nylon material, washable, colorfast, and reusable. A great tool for breeders or farmers to easily identify animals. Easy to adjust with a safety quick-release buckle, safe to wear and remove. Includes two weight record keeping charts for daily or weekly tracking. The metal D-ring allows attachment of an ID tag or leash. These puppy ID collars come in 14 different bright colors to help identify puppies and kittens easily. Ideal for pet owners and breeders to track growth, health, weight, behavior, and more. Features: 1. 14 distinct colors for easy identification of similar-looking pets. 2. High quality, well-made, soft, and adjustable for a comfortable fit. 3. Breakaway safety buckle releases under pressure, providing safety while staying secure during play. 4. Includes two weight tracking charts, ideal for monitoring pet health. 5. Easy to clean and fast drying; machine washable. 6. Suitable for small animals such as cats, kittens, hamsters, bunnies, and guinea pigs. Package includes: 14 collars and 2 paper cards. Material: high-quality soft nylon. Small: 17.8cm - 26cm length; 1.0 cm width. Medium: 21.6cm - 34cm length; 1.0 cm width. Features: easy to recognize, soft, adjustable, breakaway, safe. Colors: purple, orange, yellow, brown, black, silver, blue, fluorescent green, green, hot pink, light pink, red, sky blue, navy blue. Suitable for puppies, kittens, and small animals such as hamsters, bunnies, and guinea pigs. Note: Please measure your pet's neck circumference to ensure proper fit before purchase.