My 5e, like all the rest of the answers, is only a one model transmitter. If you are losing the connection to the last bind when you turn it off, you may need to send it in for testing. My transmitter did this and that is what the service center asked me to do. But I did not. A friend of mine loaned me his reciever and the transmitter bound to it fine. I then tried to bind back to my original reciever and it did. It remained bound to it. Too worried about it, I bought another transmitter.