Is an urn a better choice than a cremation box for a pet?

My 18-year-old cat recently had to be put to sleep, and I decided to have her cremated. I’ve never had to choose a cremation container for a pet before, and I’m not sure if a traditional urn is appropriate for a pet because it’s always used for human ashes. So, I’ve been looking into a cremation box as an alternative. What I’m worried about is that a cremation box is not as secure and durable as something like a brass urn. Is a traditional urn is better to choose than a cremation box? If you know more about this, please help… Thanks very much.