I've given up on collars. My cats are indoor only so the need isn't great. Mingo used to hide a lot so the jingling of the bell let me know where he was. Lily is a small cat, and I couldn't make the collar small enough for her. She lost it in a few days. Mingo scratched at his until it broke away three times, so I let it go. They both are microchipped if they should suddenly escape out the door.