I have two collars to move. Sportdog 400s 1. needs new battery for receiver. (you can order these) 2. this one might need a new reciever? It tends to not pick pick up transmission from remote. I have reset it a couple times but then it seems to lose it again. Called company and they said it needs a new receiver. So..two remotes and two collars. If someone wants to fix up a bit should be a good deal. Thinking $50 for both shipped.