★GREAT MATERIAL--The puppy identification collars are made of soft nylon material, is washable, colorfast and reusable. ★SATETY BUCKLE-- safe buckle releases when pressure is applied, it makes our ID collar very safe for puppies, and very convenient for you to open it. ★ADJUSTABLE SIZE--The ID collars can fit pets whose neck girth is 7.5-10.2 inches. So other small animals whose neck girth is within this size can wear. ★6 RECORD KEEPING CARDS--Record system does all pertinent information, Bottle Feeding Chart, Weight Charts (Daily&Weekly), Health Records (Vaccinations&Wormings), Whelping Details, New Owner Information.