Multi-purpose:1.These boots can keep the dog's paws warm and dry in cold winter.2.It can protect the dog's paws from being burnt in hot summer.3.It can prevent dogs from scratching carpets or wooden floors4.It can protect the dog's paws against hurt from stones, asphalt, grass etc. while walking.5.It can keep the dog's paws clean and dry on rainy days.Measure method:1) Place the pet's paws on a piece of paper and press down on the top, mimicking how the paw spreads when the dog is walking.2) Measure the paw length and width,mark the left and right sides on the paper and measure the distance between the marks.3) Choose size according to width is better.4) Choose the Right size for your dogs.Size Referance:Size 2:?2.4''x1.6'')(L*W) for Schnauzer;Bichon Frise etc.(19.8lb)Size 3:?2.5''x1.9'')(L*W) for Standard Poodle;Schnauzer etc.(Over 23lb)Size 4:?2.51''x2.24'')(L*W) for Akita;American Cooker Spaniel etc.(About 33lb dog breed)Size 5:?2.51''x2.36'')(L*W) for Border Collie;Cooke;Medium Chow Chow etc.(43lb mixed border collie;55lb American Pit Bull)Size 6:?2.83''x2.59'')(L*W) for Medium Samoyed;Husky;Labrador;Medium and large Chow Chow etc.(65lb;70lb pitbull)Size 7:?3.22''x2.91'')(L*W) for Medium Golden Retriever;Large Samoyed;Labrador etc.(75 lb GSP;90 lb German Shepherd)Size 8:?3.22''x2.99'')(L*W) for Large Golden Retriever;German Shepherd,Rottweiler;Old English Sheepdog;Alaska Malamute etc.(80lb labradoodle;90 lb Lab)Warm tips*Don't worry when your dogs start to walk with new shoes but not in a normal pace even prance.*You can try to encourage and guide your love dog to adapt to this new friend - shoes.*Though the boots are waterproof, the dog boots can not be applied in deep water or in sands, because there may be water or fine sand seepage through sewing needle holes.