It won't fall off if you adjust the inner clasp!
The collar is really good! Most people don’t notice, but inside the clasp there’s a tab that lets you adjust how easily the safety release opens.
If you leave it in the default setting, it opens right away when the cat scratches itself. But if you adjust the strength on the inner clasp, it fits perfectly around the neck without falling off, while still keeping the anti-strangulation feature active if the cat gets stuck. Totally worth it!