My dog will somehow consistently rip off her rabies tag if it is hanging from her collar. I don't know how, but she does. Every. Single. Time.
Or at least she did, until I made this. The one pictured has been on her collar since 2020, so I would say it works.
The veterinarian has a different shape for the tag every year, and so far they have all fit. To date that's been most of the lucky charms -- clover, heart, diamond, etc. they all slid right in.
The author marked this model as their own original creation.