Nicecchas, might want to read the reviews here. http://www.amazon.com/30-AMP-Portable-Surge-Protector/product-reviews/B001RPSNYC. Progressive industries seems to be a popular unit with campers. they offer a hard wired unit or one that just plugs at shore power.
It's an Autoformer that boost voltage that happen to include surge protection. It's primary job is to boost low voltage. It is good to use in front of an EMS that also includes surge protection. EMS is a 3rd piece of equipment that is often misnamed a surge protector.You may also want to consider a Hughes Autoformer. It is a basic surge protector, but it is also a power booster. It will boost the AC voltage up to 10% when needed.