I heard, not sure if its true or not, that you have to keep the original box if you have to send it in for warranty??? I wouldn't know, I have never sent mine In for warranty in the 8 years I have owned it. But, I do know the box went bye bye long ago. Very dependable unit, saved me a couple of times. I always plug it in first to the pedestal to check power at the pedestal before connecting trailer.