Collars

NECK GIRTH: Measure the circumference midway between the ears and the base of the neck, just about where the collar would sit.

CHEST GIRTH: Measure around the widest part of your Chihuahua's chest - usually right behind the front legs.
BACK LENGTH: Measure along the back, from the collar to the base of the tail.
Please give 1 to 3 cm for any error. If your dog measure between two sizes , for optimal comfort choose the larger size.