Avo wears an XS
The first measurment is for around the neck and the second measurement is for around the chest. For how to correctly measure your pet please look at the 3rd photo
To get the most out of your new harness I recommend taking off for any rough playdates or muddy adventures. When washing it is best to handwashing and lay flat when drying
You should always check your harness for wear and tear. No harness' are indestructible and it is your responsibility to check for the suitability of the harness for your dog.