Breed Examples For Dog Collars.
XXS - 7" to 11" x 13mm - tiny dogs/puppies, toy breeds, small Chihuahuas and similar sized breeds.
XS - 9" to 13" x 16mm - toy breeds, larger Chihuahuas, puppies of small to medium size first collar.
SMALL - 10" to 15" x 20mm - Border Terriers, small Westies, smallers Cocker Spaniels, Jak Russells and similar sized breeds.
MEDIUM (narrow) - 12" to 19" x 20mm - Pugs, larger Cocker Spaniels, Larger Westies, smaller Border Collies, and similar sized breeds.
MEDIUM (wide) - 12" to 19" x 25mm - Labradors, Beagles, Springer Spaniels, larger Border Collies, Staffies and similar sized breeds.
LARGE - 17" to 24" x 25mm - larger Labradors, German Shepherds, Rottweiler, Bulldogs etc.