ADJUSTABLE - Suitable for small, medium and large dogs. please look at the photo of the dog size selection instructions. DOG TAG INCLUDED - You'll never have to worry about losing your dog with this collar! It comes with an attached QR ID dog tag with address and dog documents. DURABLE - Dog collars medium is made of high quality wear-resistant nylon. With a sturdy plastic buckle, your dog will be ready for whatever the day brings. SAFETY BUCKLE - Providing a strong and reliable grip, the breakaway buckle of these collars exceeds all requirements for strength, safety and comfortable use for you and your pet. REFLECTIBLE - These collars are perfect for walks at night, to add visibility, and keep up their impeccable look even when they're dirty!