I Have both. But only put the leash on the Harness due to the Yorkies extremly fragile necks/throats. plus i'm scared of their trachea collapsing due to the collar with the leash on since My Yorkies love to tug.
I only put the collar on with their ID tags on. or I have the collars just for looks, i have the ones with the rhinestone lettering named ones.
