Like new RC PAWks dog boots are anti slip dog boot socks for dogs that provide both traction and protection for your dog's paws. Our dog was in between sizes so this was an extra pair. Information below taken from website. Suggested sizes by breed: XXS: Chihuahua, Dachshund, Havanese, Maltese, Papillon, Pomeranian, Pug, Shih Tzu, Toy Fox Terrier, Toy Poodle, Yorkie XS: Italian Greyhound, Pug, Mini Pincher S: Border Terrier, Border Terrier, Brussels Griffon, Fox Terrier, Jack Russell, Shiba Inu M: American Eskimo, Beagle, Cocker Spaniel, Standard Dachshund, Lhasa Apso, Tibetan Terrier L: Labrador, Golden Retriever, German Pointer, Pitbull XL: Great Dane, Great Pyrenees, Bull Mastiff, Newfoundland, Old English Sheepdog, Saint Bernard, Giant Schnauzer Dogs socks should fit snugly, choose a size down or if you are in between sizes choose the smaller size.