surge protector newbie

I realize that this is a very basic electrical question but I am just a bit confused. I read that you can take a 30amp surge protector with a 50amp adapter and plug it into a 50amp pedistal plug to run a 30amp camper with no problem. I need to know what is best to use if I am plugging a regular 15 or 20 volt cord into the plug of the the pedistal to run to an outdoor TV/Blu-ray DVD player, what should I use for a surge protector? I want to be sure that the electronics are protected from low/high voltage. I am looking at a Progressive Industries 30amp EMS protector for the camper but what about this cord that I want to run directly instead of running through the camper's power? Can anyone offer suggestions or explain what will work?