The boot is for my old unit because the plastic clip that the strap went through broke off. I need something for the strap to go through so I can use it as a backup if the new one ever fails.

My dogs play ruff. And my dogs have damaged a collar so it quit transmitting to open the door. So I purchased the rubber boot for it. It gives me a sense of security that the collar is protected from their ruff playing.

It's great to have everything neatly on one collar. It was awkward the first time I assembled it. And I had to take it half way apart to change the battery. It wasn't as bad as I thought it would be.
Glad I bought them.

Always great!!

I have 3 large dogs. Those collars are all at least 1" wide. This does not allow for the wider collar. Very frustrating, can't use them. I like changing designs for events and seasons, the ones here are too expensive and kinda boring.