The SP Series of commercial generators range from 1,500 to 5,500 watts, all mounted on rugged DOT certified trailers. Typically used by the construction trades, for RV and campers, hunting camps, or anywhere you need power where grid power is unavailable. These models use quality components, the inverters include a charger that allows recharging from any 120 VAC/60Hz source, and lightning arrestors are installed to help protect the electrical system.