We had the Tabcat tag on a breakaway collar. This morning we noticed Freddie didn't have his collar on. Found the Handset and started looking. Knew it was in the house somewhere. Well, it went bonkers in the basement by the Christmas boxes where the cat was yesterday while I was working in the basement. Could not find the collar. Looked in all the bags and boxes that were open. No luck. Went back to your User Guide. It suggested I mute the Handset and listen for beeps on the tag. Sure enough. It was in a cardboard box which had 4 flaps folded over, with enough of a gap for him to stick his head in and lose his collar when he pulled it out. But the gap was small enough for us not to check. Lesson learned. If the handset goes off and you still can't find the collar, turn the sound off and listen for the beep on the tag.