I'm not a collar fan for my yorkies, but just to be cute, I did try some leather-ette cheapies with rhinestone initials on them, and they flat chewed them off! If you are (and you should) using a harness rather than a collar, leather is heavier, I would go with nylon. But if you really like the leather after your puppy gets full grown get a leather one too!
I never leave a collar or harness on mine when I'm not around. I'm afraid they will get them hung on something and get hurt! |