Personally, they are cute, but I wouldn't trust them. If it's not buckled around the neck so tight their head can't get through using an unbreakable fabric and a sturdy metal buckle, I'm not going to trust it. I used to take my cats out in both a harness and a secondary collar, and I ran a "panic" line from the collar to the leash end, so if they got out of the harness, I'd still have them by the collar. I've since learned to trust my sturdy 5/8 inch nylon dog collars.
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