Originally Posted by Paul O.
Both zinc and graphite are conductors, so I bet this is only suitable for a high power connection that is made once and left alone. Not a switch.
I used contact cleaner for the switch, not Ox-Gard. I used Ox-Gard on the base of the bulb (just a thin film). It's primary purpose is to prevent oxidation (hence, the name) and it does help prevent corrosion. Try a little on the base of one of your trailer's tail light
bulbs and then compare to an untreated bulb a year or so later.
By the way, a little dab works great in the female part of the tug to trailer connection, which often becomes a corroded mess in short order.
One caution however, since it is a conductive paste, it can cause a short if over applied.