We recommend:
1" (25 mm) SMALL for cats, puppies, and dogs under 30lbs = 13kg [Chihuahua, Pomeranian, Yorkshire Terrier, Toy Poodle, Dachshund]
1.20" (30 mm) MEDIUM for dogs 30-60 lbs = 13-27kg [lbshiba, Miniature Schnauzer, Beagle]
1.35" (34 mm) LARGE for dogs 60+ lbs= 27+ kg [Golden Retriever, Dalmatian, Standard Poodle]
You can choose a smaller or a bigger tag if you would like the tag be less or more visible on the pet body.