Free is good however I doubt it will work on your 50amp towable. Since the unit only addresses low park voltage and has a bad park circuit detector, it seems to be of little use unless you frequent parks that are grossly underpowered and have "fugazy" wiring. Just a suggestion, you might he better off with a Progressive Ind PMS rather than just a voltage supplement. My reasoning behind that is that the Autoformer trades Amps for volts. If you need 50a and only have 30a, I cannot see how you would be served with less than 30a.
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